# Deadly MWBC's



## Cletis (Aug 20, 2010)

I talked with engineer that did these plans on friday. I said what's up with the no neutral sharing. He said he doesn't spec' deadly mwbc's and went into a rant. 

Thoughts ?


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## BBQ (Nov 16, 2010)

As long as you bid it expecting all two wire circuits all is good.


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## Cletis (Aug 20, 2010)

*yep*

I did bid it at that. Are you all seeing engineer's spec'ing this alot nowadays ?? I've talked to 3 now that want no shared neutrals. They all go into how dangerous it is.


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## Mr Rewire (Jan 15, 2011)

This is addressed in the NEC by requiring MWBC to be on handle tied breakers.


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## BBQ (Nov 16, 2010)

Cletis said:


> I did bid it at that. Are you all seeing engineer's spec'ing this alot nowadays ?? I've talked to 3 now that want no shared neutrals. They all go into how dangerous it is.


Yeah, there are a lot of ignorant folks in our profession. 



> This is addressed in the NEC by requiring MWBC to be on handle tied breakers.


Point proven


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## mattsilkwood (Sep 21, 2008)

Mr Rewire said:


> This is addressed in the NEC by requiring MWBC to be on handle tied breakers.


 And that's one of them that I don't agree with.
If you are properly trained there is not a thing in the world wrong with a MWBC, if you're not properly trained you have no business working on an electrical system.


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## BBQ (Nov 16, 2010)

mattsilkwood said:


> If you are properly trained there is not a thing in the world wrong with a MWBC, if you're not properly trained you have no business working on an electrical system.


I agree, but I think you will find most EEs avoid them for other reasons such as harmonic current issues and poor installation practices leading to open neutrals and fried equipment.

I happen to love MWBCs but many EEs do not.


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## Mr Rewire (Jan 15, 2011)

mattsilkwood said:


> And that's one of them that I don't agree with.
> If you are properly trained there is not a thing in the world wrong with a MWBC, if you're not properly trained you have no business working on an electrical system.


 Open up a 12x12 Jbox with sewveral hots and neutrals present and tell me which wire are on MWBC and which are not. Thats like saying if you are trained to work on a lift you don't need a safety harness. This was one of the smarter code changes as it was a safety issue and not selling a product.


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## 480sparky (Sep 20, 2007)

Mr Rewire said:


> Open up a 12x12 Jbox with sewveral hots and neutrals present and tell me which wire are on MWBC and which are not. Thats like saying if you are trained to work on a lift you don't need a safety harness. This was one of the smarter code changes as it was a safety issue and not selling a product.


"Qualified Personel" will know enough to readily identify a MWBC, and fully understand the dangers involved with working on them. A qualified person would have no problems working in a 12x12 jbox that has 6 blacks, 6 reds, 6 blues and 6 whites coming into it.

The 'common disconnect' rule was put in place because so many *un*qualified people were working on them. In effect, the CMP 'dummied down' the NEC.


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## nolabama (Oct 3, 2007)

Who hires "qualified personel" anymore...


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## mattsilkwood (Sep 21, 2008)

BBQ said:


> I agree, but I think you will find most EEs avoid them for other reasons such as harmonic current issues and poor installation practices leading to open neutrals and fried equipment.
> 
> I happen to love MWBCs but many EEs do not.


 I like to call it the refer madness effect. 
As for the poor installation, I don't see that as an NEC problem.


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> Open up a 12x12 Jbox with sewveral hots and neutrals present and tell me which wire are on MWBC and which are not.


Do you have an ammeter of some type?

A qualified person knows to use it before breaking a connection in a box like you describe.


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## BBQ (Nov 16, 2010)

mattsilkwood said:


> As for the poor installation, I don't see that as an NEC problem.


Neither do I.

But engineers do see that as a problem on jobs they have a say in.


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## Mr Rewire (Jan 15, 2011)

480sparky said:


> "Qualified Personel" will know enough to readily identify a MWBC, and fully understand the dangers involved with working on them. A qualified person would have no problems working in a 12x12 jbox that has 6 blacks, 6 reds, 6 blues and 6 whites coming into it.
> 
> The 'common disconnect' rule was put in place because so many *un*qualified people were working on them. In effect, the CMP 'dummied down' the NEC.


 And I am sure every 12 x 12 j box is set up that way.  Real world you pop a jbox open it may have brown .blue,orange and look like a colorful spider web in a cherry tree. As a service electrician I would much perfer being able to shut off a handle tied breaker than to try and search for the three breaker that may not even be in the same panel section. So in your opinion eliminating a potential hazard is dumbing down. :no:


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## Mr Rewire (Jan 15, 2011)

BBQ said:


> Do you have an ammeter of some type?
> 
> A qualified person knows to use it before breaking a connection in a box like you describe.


 And what would that do exactly to prevent an electrocution from opening a MWBC neutral. I sit at the feet of the master seeking his great knowledge.


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> And I am sure every 12 x 12 j box is set up that way.  Real world you pop a jbox open it may have brown .blue,orange and look like a colorful spider web in a cherry tree. As a service electrician I would much perfer being able to shut off a handle tied breaker than to try and search for the three breaker that may not even be in the same panel section. So in your opinion eliminating a potential hazard is dumbing down. :no:


So you are saying when you are trying to service an installation done by hacks that you would count on them to follow the rule for a common disconnect. 

Assuming this spider web of a box has more than one circuit what does a handle tie do for you?


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## 480sparky (Sep 20, 2007)

Mr Rewire said:


> And I am sure every 12 x 12 j box is set up that way.  Real world you pop a jbox open it may have brown .blue,orange and look like a colorful spider web in a cherry tree. As a service electrician I would much perfer being able to shut off a handle tied breaker than to try and search for the three breaker that may not even be in the same panel section. So in your opinion eliminating a potential hazard is dumbing down. :no:


You're just being lazy. You simply want someone else to make your job easier.


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## mattsilkwood (Sep 21, 2008)

Mr Rewire said:


> And I am sure every 12 x 12 j box is set up that way.  Real world you pop a jbox open it may have brown .blue,orange and look like a colorful spider web in a cherry tree. As a service electrician I would much perfer being able to shut off a handle tied breaker than to try and search for the three breaker that may not even be in the same panel section. So in your opinion eliminating a potential hazard is dumbing down. :no:


I have seen poor installation of wirenuts cause damage and create a shock hazard. Should we ban them too?


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> Open up a 12x12 Jbox with sewveral hots and neutrals present and tell me which wire are on MWBC and which are not.





BBQ said:


> Do you have an ammeter of some type?
> 
> A qualified person knows to use it before breaking a connection in a box like you describe.





Mr Rewire said:


> And what would that do exactly to prevent an electrocution from opening a MWBC neutral.



Go have a cup of coffee, wake up and think on it.



> I sit at the feet of the master seeking his great knowledge.


You could just ask a first year helper to explain it to ya.


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## Mr Rewire (Jan 15, 2011)

BBQ said:


> So you are saying when you are trying to service an installation done by hacks that you would count on them to follow the rule for a common disconnect.
> 
> Assuming this spider web of a box has more than one circuit what does a handle tie do for you?


 A hack wouldn't use a handle tied breaker.The point is in the real world just looking in the jbox you cannot identlfy which wire goes to which neutral or if that neutral is even on a MWBC. I dont see how requiring MWBC to be handle tied is a bad idea .


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## drsparky (Nov 13, 2008)

I agree with the EE on this one.


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## Mr Rewire (Jan 15, 2011)

BBQ said:


> Go have a cup of coffee, wake up and think on it.
> 
> 
> 
> You could just ask a first year helper to explain it to ya.


 well just say you don't know and be done. you just realized you jumped out with no chute and are deflecting on the way down so nobody sees your splat :laughing::laughing:


An ameter will only be effective if load ispresent at the time of the reading. Lights off no load no amp reading unhook neutral someone turns lights on load bad juju.


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## 480sparky (Sep 20, 2007)

Mr Rewire said:


> ...........The point is in the real world just looking in the jbox you cannot identlfy which wire goes to which neutral or if that neutral is even on a MWBC. ......... .


So _you_ need to _figure it out_, not get handed a solution on a silver platter. Do more than look. THINK!


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## Podagrower (Mar 16, 2008)

Mr Rewire said:


> This was one of the smarter code changes as it was a safety issue and not selling a product.


Copper wire is not a product?


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## Mr Rewire (Jan 15, 2011)

480sparky said:


> So _you_ need to _figure it out_, not get handed a solution on a silver platter. Do more than look. THINK!


 How dare they make our job easier and safer. :no:


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## Mr Rewire (Jan 15, 2011)

Podagrower said:


> Copper wire is not a product?


 you were making a point ? :jester:


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> The point is in the real world just looking in the jbox you cannot identlfy which wire goes to which neutral or if that neutral is even on a MWBC.


I agree.

Even in a j-box full of all two wire circuits you can often not tell which neutral goes with which hot.

That is where the skill comes in.



> I dont see how requiring MWBC to be handle tied is a bad idea


I will tell you why I think it is, no one has to agree with me but it is what I think.

An electrician goes into a office building for a service call, lets say that they need to change out a broken receptacle. They put a tracer in the outlet and find the circuit in the panel, but it is just one pole of a two or three pole or handled tied breaker. 

They look at the panel schedule and realize that when they shut the circuit off they need to work on they will also be shutting off one or two other circuits that may be needed.

Now what?

Do they reschedule the work for after hours when the other circuits are not in use?

OR

Do they say screw it and work it hot?

My point is, if the point of the handle tie was to protect us, it also has the opposite effect.


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## Lone Crapshooter (Nov 8, 2008)

I have to agree that the new MWBC requirements are to compensate for unqualified people. 
The one circuit one neutral really is just as dangerous . How are you going to tell out in the field what neutral goes with what hot unless you have a ammeter. 

My personal policy only splice neutrals with the appropriate hot. But that only works to a point. 
When I have to splice everything I will put some tape around the pairs.


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> well just say you don't know and be done.


Why would I lie, I do know.



> you just realized you jumped out with no chute and are deflecting on the way down so nobody sees your splat


Oh I get it, you are trying to say I don't know what I am talking about. 




> An ameter will only be effective if load ispresent at the time of the reading. Lights off no load no amp reading unhook neutral someone turns lights on load bad juju.


Very true, and you don't really think I am unaware of that.

There are these things called wire nuts, you break the splice, you cap both parts and work to verify you have the neutral you are looking for.

Or do _you_ just grab any neutral for a new circuit?

Keep in mind the handle ties do nothing to help you identify a neutral.:no:


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## RePhase277 (Feb 5, 2008)

No matter how many rules you throw at one, a jackleg is still a jackleg. He will hack up a two-wire circuit just a fast as a 3- or 4-wire. Restricting quality craftsmen from doing their job does nothing for a hack, because only the craftsman follows the rules.


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## BBQ (Nov 16, 2010)

So you have to work in this box










How are handle ties going to help find the neutral that goes with the hot?


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## Awg-Dawg (Jan 23, 2007)

BBQ said:


> Do they reschedule the work for after hours when the other circuits are not in use?
> 
> OR
> 
> ...


I agree with you on this one.

I also think that guys will just take the handle tie off to work on it.


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## 480sparky (Sep 20, 2007)

Mr Rewire said:


> How dare they make our job easier and safer. :no:


Yeah! Let's require a disconnect at every switch, receptacle, pole light, light fixture, etc. so lazy technicians don't have to find breakers and won't have to replace a device hot!

I propose there should never be more than three circuits in a raceway or box. It's just too mind-boggling to figure any more than that out.

Let's require every conductor to be fully labeled at every junction box, device box, and splice. Ever wire should have something like "Office lights, circuit #17/panel LP3B, 277v (location: 3rd floor mezzanine), fed from jbox 14' at 285°, controlled from switch box on SE wall, 3rd switch from left."

Every install should have a map of how every circuit is routed, where every box is located, and an amp reading listed for every conductor in every box on every circuit. (B4T will be happy to propose this one!)

Let's require all electrical use cease at 5PM and resume at 7AM Monday-Friday, and no electricity can be used on weekends. I hate after-hours service calls. Besides, working tired is working unsafe!

I hate doing underground, so let's abolish buried cables & raceways. I also don't like working on tall ladders, so all installations should not exceed 12' AFF.


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## Mr Rewire (Jan 15, 2011)

BBQ said:


> I agree.
> 
> Even in a j-box full of all two wire circuits you can often not tell which neutral goes with which hot.
> 
> ...


 In your senario our techs would inform the person in charge that other circuits would be turned off. If the customer desired an after hours call it would be set up and they would be billed for this call and the after hours call.

Working hot is stupid and it is hard to fix stupid but I see your point.But the code is looking at safety and handle tied breakers provide a safer install.


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## BBQ (Nov 16, 2010)

Mr Rewire said:


> In your senario our techs would inform the person in charge that other circuits would be turned off.


I expect the same from our guys.



> But the code is looking at safety and handle tied breakers provide a safer install.



I disagree with that, I think it is a wash.


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## Mr Rewire (Jan 15, 2011)

BBQ said:


> I expect the same from our guys.
> 
> 
> 
> ...


 well you only have to put on one lockout, :thumbsup:


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## Cletis (Aug 20, 2010)

*Labeled*



BBQ said:


> I agree.
> 
> Even in a j-box full of all two wire circuits you can often not tell which neutral goes with which hot.
> 
> ...


Since when are panel schedules correct ? :laughing:


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## 480sparky (Sep 20, 2007)

Cletis said:


> Since when are panel schedules correct ? :laughing:


They're required to be. Therefor, they are. 408.4.


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## Cletis (Aug 20, 2010)

*ok*



480sparky said:


> They're required to be. Therefor, they are.


ok. Then every job I'll shut off breaker that is labeled for what I need to work on and see what happens....:laughing:


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## BBQ (Nov 16, 2010)

Cletis said:


> Since when are panel schedules correct ? :laughing:


Sorry, I am kind of spoiled,:laughing: I work in a lot of places with pretty good panel schedules. That means they are like 75% correct and are more descriptive than

1-Lites
3-Plugs
5-Plugs
7-Lites
9-Bedroom
11-Hall
13-Pig


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## 480sparky (Sep 20, 2007)

Cletis said:


> ok. Then every job I'll shut off breaker that is labeled for what I need to work on and see what happens....:laughing:


Works for me. If it's marked, "Dave's Bedroom", and Dave no longer lives there, you'll need to track Dave down and ask him which room was his, though.


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## Cletis (Aug 20, 2010)

*I*



BBQ said:


> Sorry, I am kind of spoiled,:laughing: I work in a lot of places with pretty good panel schedules. That means they are like 75% correct and are more descriptive than
> 
> 1-Lites
> 3-Plugs
> ...


My ratio is inverse yours


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## 480sparky (Sep 20, 2007)

BBQ said:


> Sorry, I am kind of spoiled,:laughing: I work in a lot of places with pretty good panel schedules. That means they are like 75% correct and are more descriptive than
> 
> 1-Lites
> 3-Plugs
> ...



I like the ones where 80% of the breakers are labeled, "General". :laughing:


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## BBQ (Nov 16, 2010)

Cletis said:


> My ratio is inverse yours


Inverse, is that like when we sing together?


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## BBQ (Nov 16, 2010)

480sparky said:


> I like the ones that 80% of the breakers are labeled, "General". :laughing:


:laughing:

15- stuff
17- things


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## 480sparky (Sep 20, 2007)

BBQ said:


> Inverse, is that like when we sing together?


No, that's _harmony_.


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## BBQ (Nov 16, 2010)

480sparky said:


> No, that's _harmony_.


Me and Cletis, ebony and ivory. :laughing:


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## 480sparky (Sep 20, 2007)

BBQ said:


> Me and Cletis, ebony and ivory. :laughing:



Skeeter and Bubba. :thumbsup:


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## BBQ (Nov 16, 2010)

480sparky said:


> Skeeter and Bubba. :thumbsup:


I have always wanted to drive an early 60s tow truck and be called Skeeter. :laughing:


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## mattsilkwood (Sep 21, 2008)

BBQ said:


> I have always wanted to drive an early 60s tow truck and be called Skeeter. :laughing:


 I don't know, you seem more lika a "Mater" to me.:laughing:


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## Cletis (Aug 20, 2010)

*?*



BBQ said:


> Inverse, is that like when we sing together?


Actually, I sing in a band and i'm pretty good. Mostly heavy metal, lot's of beatles, barry manilow, etc...



BBQ said:


> Me and Cletis, ebony and ivory. :laughing:


Which of us is ebony?



480sparky said:


> Skeeter and Bubba. :thumbsup:


Who is skeeter and who is bubba ?


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## mattsilkwood (Sep 21, 2008)

Cletis said:


> Actually, I sing in a band and i'm pretty good. Mostly heavy metal, lot's of beatles, barry manilow, etc...


 I gotta say, that's one hell of a playlist.:laughing:


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## BBQ (Nov 16, 2010)

Cletis said:


> Actually, I sing in a band and i'm pretty good. Mostly heavy metal, lot's of beatles, barry manilow, etc...













> Which of us is ebony?


Your call.





> Who is skeeter and who is bubba ?


I already called Skeeter.


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## knowshorts (Jan 9, 2009)

And doesn't the EE usually spec out conduit rather than MC? With separate neutrals, there would be more heat, no?


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## BBQ (Nov 16, 2010)

mattsilkwood said:


> I gotta say, that's one hell of a playlist.:laughing:


I would like to see the segway between Motorhead's Ace of Spades and Barry's 'Mandy' :laughing:


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## B W E (May 1, 2011)

BBQ said:


> I agree.
> 
> Even in a j-box full of all two wire circuits you can often not tell which neutral goes with which hot.
> 
> ...


Measure the load. If its minimal, pull the dead front off and pull the wire off the breaker.

Not a recommend method, but it would work.


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## B W E (May 1, 2011)

BBQ said:


> Why would I lie, I do know.
> 
> Oh I get it, you are trying to say I don't know what I am talking about.
> 
> ...


 when you turn off the handle-tied breaker, the load on the neutral will drop to zero. So, it kinda does make it possible to identify the neutral.


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## BBQ (Nov 16, 2010)

B W E said:


> when you turn off the handle-tied breaker, the load on the neutral will drop to zero. So, it kinda does make it possible to identify the neutral.


And that is going to help how?

Are you assuming all other neutrals in the box have constant loads on them?

As Rewire pointed out the loads may go on and off.


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## BBQ (Nov 16, 2010)

B W E said:


> Measure the load. If its minimal, pull the dead front off and pull the wire off the breaker.
> 
> Not a recommend method, but it would work.


Thanks for proving the point that this rule pushes guys toward unsafe work practices. :thumbsup:


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## hardworkingstiff (Jan 22, 2007)

Cletis said:


> I talked with engineer that did these plans on friday. I said what's up with the no neutral sharing. He said he doesn't spec' deadly mwbc's and went into a rant.
> 
> Thoughts ?


Does that mean you have to have a separate neutral for each phase conductor back to the PoCo transformer? ... Just saying...


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## B W E (May 1, 2011)

BBQ said:


> And that is going to help how?
> 
> Are you assuming all other neutrals in the box have constant loads on them?
> 
> As Rewire pointed out the loads may go on and off.


If you see a load on a neutral that reacts when the breaker is turned off, it helps a lot.

Say you have 6 neutrals. Measure them all, and list them a-f.

Say you have (12) handle-tied breakers. Label them 1-6.

Turn off #1, check neutral loads and find one that is different. Repeat for the rest.


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## BBQ (Nov 16, 2010)

B W E said:


> If you see a load on a neutral that reacts when the breaker is turned off, it helps a lot.
> 
> Say you have 6 neutrals. Measure them all, and list them a-f.
> 
> ...


So in this case the handle ties reduce the number of possible tries from 12 down to 6.

I guess you got me there. :laughing:


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## Cletis (Aug 20, 2010)

*Done*



BBQ said:


> I would like to see the segway between Motorhead's Ace of Spades and Barry's 'Mandy' :laughing:


I have a triple I like particularly. Green Day (Welcome to Paradise), GnR I used to love her, Can't smile without you, then finish with blackbird.


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## B W E (May 1, 2011)

BBQ said:


> Thanks for proving the point that this rule pushes guys toward unsafe work practices. :thumbsup:


That's no more unsafe then pulling a wire out of a back stabbed plug. But, I wasn't saying Anything about it being safe, just do-able.


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## micromind (Aug 11, 2007)

In my mind, the handle-tie and/or the EEs 'no MWBC' requirements were enacted for two reasons;

1) I'm pretty sure the copper industry backed it as it will encourage the use of more wire. A lot more.

2) Once again, a law was enacted to allow fools to become even more foolish. It's part of the governments 'dumb 'em down' project. Uninformed people will do exactly as they are told, smart people tend to question leadership.

Although this is a very small point, on a national level it adds up; MWBCs have a slight efficiency advantage over two-wire ones. There is less heat dissipated in the neutral conductors.

In my opinion, if you lack the ability to handle a MWBC, you have no place in the electrical trade.


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## BBQ (Nov 16, 2010)

B W E said:


> That's no more unsafe then pulling a wire out of a back stabbed plug. But, I wasn't saying Anything about it being safe, just do-able.


Much of this thread has been about the code requiring handle ties to increase safety.

If someone is pulling panel covers off because of this handle tie rule that supports my point that the handle tie rule does not increase safety it actually steers electricians into doing thing they should not.


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## BBQ (Nov 16, 2010)

Cletis said:


> I have a triple I like particularly. Green Day (Welcome to Paradise), GnR I used to love her, Can't smile without you, then finish with blackbird.


I want a picture of what the audience looks like. :laughing::laughing:


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## joethemechanic (Sep 21, 2011)

I think the safest solution would to just pull the primary cutout on the transformer and ground it.

That MWBC coming over from the pole is dangerous


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## BBQ (Nov 16, 2010)

joethemechanic said:


> I think the safest solution would to just pull the primary cutout on the transformer and ground it.
> 
> That MWBC coming over from the pole is dangerous


Look at that, we agree. Best to cut the drop down entirely. :laughing:


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## janagyjr (Feb 7, 2011)

BBQ said:


> I agree.
> 
> Even in a j-box full of all two wire circuits you can often not tell which neutral goes with which hot.
> 
> ...


I've not worked a MWBC, but there is a lot I haven't done. They look confusing enough in the text book, though.



BBQ said:


> So you have to work in this box
> 
> 
> 
> ...


That's a mess.


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## 480sparky (Sep 20, 2007)

BBQ said:


> Look at that, we agree. Best to cut the drop down entirely. :laughing:



Electricity is deadly. It should be abolished.:whistling2:


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## drsparky (Nov 13, 2008)

Why don't like shared neutrals.

1. Three circuit must be shut down for maintenance of one device. Takes a lot more time to coordinate shutting down computers etc.
2. Power factor differences in shared circuits may increase load on neutrals. 
3. Single point failure may cause damage to equipment.
4. A lot of equipment has internal fusing only rated in the 120v range, an open neutral may impart 240 across fuse.


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## B W E (May 1, 2011)

BBQ said:


> So in this case the handle ties reduce the number of possible tries from 12 down to 6.
> 
> I guess you got me there. :laughing:


Never mind. You're not getting it. 6 two pole (handle tied) breakers, 6 neutrals. Go through each breaker once and you have all the neutrals identified.


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## 76nemo (Aug 13, 2008)

Cletis said:


> I have a triple I like particularly. Green Day (Welcome to Paradise), GnR I used to love her, Can't smile without you, then finish with blackbird.


 
Metal followed up by Blackbird, huh?

"Take these broken wings and learn to DIE"?????????????

What if an encore is requested man?


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## B W E (May 1, 2011)

BBQ said:


> Much of this thread has been about the code requiring handle ties to increase safety.
> 
> If someone is pulling panel covers off because of this handle tie rule that supports my point that the handle tie rule does not increase safety it actually steers electricians into doing thing they should not.


Gotcha. That's true.


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## Cletis (Aug 20, 2010)

*similar*



76nemo said:


> Metal followed up by Blackbird, huh?
> 
> "Take these broken wings and learn to DIE"?????????????
> 
> What if an encore is requested man?


I do one similar to this...

http://www.youtube.com/watch?v=t5kqe3ku2c8


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## 76nemo (Aug 13, 2008)

Cletis said:


> I do one similar to this...
> 
> http://www.youtube.com/watch?v=t5kqe3ku2c8


 
That sounds like Godflesh.

Damn son, maybe the Beatles are bigger than Jesus:laughing:


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## Cletis (Aug 20, 2010)

*Louis Armstrong*

Check this one and the other ones on right. this one is best ...

http://www.youtube.com/watch?v=G_mBUYyeYMU


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## crosport (Apr 4, 2010)

Eliminate M.W.B.Cs.Why on earth would you?The whole point of them is too make it an easier, quicker more efficient install.Use em all the time on non computer or non electronic gear circuits.In Canada for the most part we don't have to install tie handles.


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## Big John (May 23, 2010)

BBQ said:


> ....Now what?
> 
> Do they reschedule the work for after hours when the other circuits are not in use?
> 
> ...


Option C: They say "If I wedge a screwdriver in there I can pop this stupid handle tie right off!" :whistling2:

-John


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## Vintage Sounds (Oct 23, 2009)

MWBCs are awesome and I'm glad the CEC has no handle tie rule except for split receptacles.

Last time I was doing housing I ran 3-conductor in as many places as I could. Fridge/dishwasher, microwave/warming drawer, garage general receps/central vacuum recep, furnace/water heater, basement receps/sump pump, living room receps/electric fireplace recep. The boss thought it was a little unorthodox but didn't object. I made rock solid connections and perfect twists, and marked on the panel the circuits that shared a neutral which a real electrician would understand. Beyond that who cares if some HO wants to go around opening splices...equipment potentially frying is a possible consequence of messing with something that they are unqualified to be poking around in.


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## gold (Feb 15, 2008)

480sparky said:


> Let's require every conductor to be fully labeled at every junction box, device box, and splice. Every wire should have something like "Office lights, circuit #17/panel LP3B, 277v (location: 3rd floor mezzanine), fed from jbox 14' at 285°, controlled from switch box on SE wall, 3rd switch from left."
> 
> .


OKay. I'm down. :thumbsup::thumbsup:


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## 220/221 (Sep 25, 2007)

Cletis said:


> I did bid it at that. Are you all seeing engineer's spec'ing this alot nowadays ?? I've talked to 3 now that want no shared neutrals. They all go into how dangerous it is.


I can agree with the spec. Although not physically dangerous, a lot of damage _can _happen. It's a more secure system and better in the long term.

I saw $14K worth of communication equipment burn up from a loose wirenut. In the same building, I was troubleshooting, removed a 4S box cover and the neutral nut came loose (not off) and sizzled a bit. I heard the copy machine below me start to twitch and was able to avoid any damage.


In a resi setting, there is typically only one conection (besides the bus connection) that will cause any issues. In a commercial setting there may be a ton of them. Also, things in a commercial building are always getting reworked over the years.


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## guest (Feb 21, 2009)

I burned up my Thanks button on this thread..maybe it was wired with a MWBC. :laughing:

BBQ has probably been waiting anxiously for me to chime in on this one, so I will. :thumbsup:

1: I do not think MWBC's are "deadly." 
2: They have a place in everyday installations and there are millions of them running trouble-free and will continue to be trouble-free for years. 
3: That said, I personally do not use them for any audio or video equipment circuits due to several problems I have had with them in the past. For lighting, general purpose recepts and motor loads even I spec them. 


Most importantly, BBQ is spot on with the FACT that the Code Requirement for handle ties promotes even more dangerous practices and does NOTHING to enhance safety.


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## Magnettica (Jan 23, 2007)

Cletis said:


> I talked with engineer that did these plans on friday. I said what's up with the no neutral sharing. He said he doesn't spec' deadly mwbc's and went into a rant.
> 
> Thoughts ?


Yes.... his house must be a ticking time bomb with that 3-wire supply source.


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## joethemechanic (Sep 21, 2011)

So when you MWBC haters install a sub panel, how many neutrals do you run from the main panel?


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## joethemechanic (Sep 21, 2011)

Hey, if I install a MWBC and use a fuse panel, do I have to tie the fuses together?


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## BBQ (Nov 16, 2010)

joethemechanic said:


> Hey, if I install a MWBC and use a fuse panel, do I have to tie the fuses together?


You would have to install a 2 or 3 pole switch at the panel.


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## Big John (May 23, 2010)

joethemechanic said:


> So when you MWBC haters install a sub panel, how many neutrals do you run from the main panel?


I just put a bonding jumper in the sub, and it saves me from potential open-neutrals. :whistling2:

I do agree with _mxslick_ though that on very expensive/critical stuff, I won't use a MWBC just because I don't trust that some goober not to open it. But that's a design choice and shouldn't be code. 

-John


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## joethemechanic (Sep 21, 2011)

Big John said:


> I just put a bonding jumper in the sub, and it saves me from potential open-neutrals. :whistling2:
> 
> I do agree with _mxslick_ though that on very expensive/critical stuff, I won't use a MWBC just because I don't trust that some goober not to open it. But that's a design choice and shouldn't be code.
> 
> -John


Have you ever grabbed "something like a neutral" out of the pecker head of a motor that is wound bringing 12 leads out?

Things really go to chit if someone shuts the motor off though


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## Big John (May 23, 2010)

Nope, not even sure how that would work. 

Only way I know you can make a neutral is with a zig-zag transformer, but I've never had to do that either. 

-John


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## joethemechanic (Sep 21, 2011)

Big John said:


> Nope, not even sure how that would work.
> 
> Only way I know you can make a neutral is with a zig-zag transformer, but I've never had to do that either.
> 
> -John


Yeah if it's got 12 leads going into the peckerhead, and it is connected in a wye and being fed 208 V. Your 10-11-12 connection becomes a neutral

Wired delta you can create a kind of high leg thing, but I'm too lazy to draw it out.

Pull the rotor out of the motor, and your neutral thingy is still a neutral, and what you have is more akin to a transformer.


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## Meadow (Jan 14, 2011)

The handle ties are a pain but sadly we have to deal with them as a result of the code making panels starting to realize that many times MWBC are falling into the custody of Half-baked intellectuals.

The biggest issue I see in MWBC are hots on the same phase. To often the neutral looks like Sunday bacon. The second and less common (but yes Ive seen it too) are people opening the splice live and sizzling equipment. 

Multiply the issue with all the buildings and pompous goons... The NEC will eventually be a step by step installation guide:laughing:


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## cultch (Aug 2, 2011)

I could be wrong but...It looks as if whatever is that cycles leading cause of fire/failure ect will get a code to try and correct it. As time goes on it will just build and build. Obviously not too many codes being removed. Anybody remember one being removed btw?


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## kbatku (Oct 18, 2011)

When we do residential MWBC's we usually land the 3 wire in a box that won't get messed with (we hope) - behind the reefer, in the box for the built-in micro, and under the sink (DW,DISP,Insta-hot). 

Theory being that people will be far less likely to ever open up a box that's hard to get at and mess with the make-ups.


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## brian john (Mar 11, 2007)

meadow said:


> The handle ties are a pain but sadly we have to deal with them as a result of the code making panels starting to realize that many times MWBC are falling into the custody of Half-baked intellectuals.
> 
> The biggest issue I see in MWBC are hots on the same phase. To often the neutral looks like Sunday bacon. The second and less common (but yes Ive seen it too) are people opening the splice live and sizzling equipment.
> 
> Multiply the issue with all the buildings and pompous goons... The NEC will eventually be a step by step installation guide:laughing:


It is IMO, it is the sissification of the NEC (NEC FOR DUMMIES), for those that can’t grasp basic electrical installation practices.


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## brian john (Mar 11, 2007)

Mr Rewire said:


> And I am sure every 12 x 12 j box is set up that way.  Real world you pop a jbox open it may have brown .blue,orange and look like a colorful spider web in a cherry tree. As a service electrician I would much perfer being able to shut off a handle tied breaker than to try and search for the three breaker that may not even be in the same panel section. So in your opinion eliminating a potential hazard is dumbing down. :no:



Please tell me you have more knowledge than this quotes seem to point out. You seem to have the business end wrapped up fairly well is electrical knowledge your Achilles heel?


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## Big John (May 23, 2010)

joethemechanic said:


> Yeah if it's got 12 leads going into the peckerhead, and it is connected in a wye and being fed 208 V. Your 10-11-12 connection becomes a neutral...


 I get where you're going with this, but I can't imagine what that would do to a running motor. 

I guess with no mechanical load on the motor, it would pass all the current the motor was using, plus the neutral load current on the Y, through the stator? Sounds like some serious MacGyver chit. 

-John


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## nolabama (Oct 3, 2007)

Big John said:


> I get where you're going with this, but I can't imagine what that would do to a running motor.
> 
> I guess unloaded it would pass all the current the motor was using, plus the neutral load current on the Y, through the stator? Sounds like some serious MacGyver chit.
> 
> -John


I would like to see that in real life.


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## Mr Rewire (Jan 15, 2011)

brian john said:


> Please tell me you have more knowledge than this quotes seem to point out. You seem to have the business end wrapped up fairly well is electrical knowledge your Achilles heel?


 Which parts went over your head?


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## BBQ (Nov 16, 2010)

brian john said:


> Please tell me you have more knowledge than this quotes seem to point out. You seem to have the business end wrapped up fairly well is electrical knowledge your Achilles heel?





Mr Rewire said:


> Which parts went over your head?


Rewire, seriously your post makes you look the fool, you know, everyone of us here knows, Brian would clean your clock when it comes to electrical knowledge. To even try to hint otherwise is simply ridiculous.

You giving Brian a hard time is like Peewee Herman giving Chuck Norris a hard time. :laughing:


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## BBQ (Nov 16, 2010)

Big John said:


> I get where you're going with this, but I can't imagine what that would do to a running motor.
> 
> I guess with no mechanical load on the motor, it would pass all the current the motor was using, plus the neutral load current on the Y, through the stator? Sounds like some serious MacGyver chit.


A motor is much like a rotating transformer.


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## cdslotz (Jun 10, 2008)

> Are you all seeing engineer's spec'ing this alot nowadays ?? I've talked to 3 now that want no shared neutrals. They all go into how dangerous it is.


Yes I do see a lot of EE's requiring this. Even if they don't specifically spec no shared neutrals, I now estimate everything with dedicated neutrals. I never see engineered panel schedules with tied breakers, so i assume their intent is no shared neutrals. 
Besides, I think the idea of handle ties on a MWBC is a terrible idea. In an office with 277V lighting, you can have a whole floor on 3 circuits. A short or an accidental turning off the breaker can put the whole floor in the dark.
On remodel of offices, complying with mwbc code can be a nightmare.


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## brian john (Mar 11, 2007)

BBQ said:


> *A motor is much like a rotating transformer*.


In my search for some information on GFP issues I was having with that chiller, I read a paper by an engineer (that seemed to really know his stuff) and he said the exact same thing.


----------



## BBQ (Nov 16, 2010)

cdslotz said:


> Besides, I think the idea of handle ties on a MWBC is a terrible idea. In an office with 277V lighting, you can have a whole floor on 3 circuits. A short or an accidental turning off the breaker can put the whole floor in the dark.


A man who lives in the real world. :thumbsup:

And what you say is becoming even more true with the energy efficient lighting, it is really tempting to run a 277 volt circuit at say 10-13 amps of load and pick up a crap load of lights, as you said often you could carry an entire floor on one circuit.


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## brian john (Mar 11, 2007)

I have no problem with engineers or customers specifying NO MWBC. Though in a “GREEN WORLD” it does waste copper.

The only thing that gets me is some of the excuses I hear, for the specifications requiring MWBC.


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## jmsmith (Sep 10, 2011)

joethemechanic said:


> Yeah if it's got 12 leads going into the peckerhead, and it is connected in a wye and being fed 208 V. Your 10-11-12 connection becomes a neutral
> 
> Wired delta you can create a kind of high leg thing, but I'm too lazy to draw it out.
> 
> Pull the rotor out of the motor, and your neutral thingy is still a neutral, and what you have is more akin to a transformer.


A wye-connected motor, the wye is nothing more than a point of connection that is there to allow the winding currents to be in a balanced state. It basically is not a neutral, per say, but a point that is meant to provide a voltage reference for the windings. Any kin to it being neutral would be kinda like an intentionally created "floating neutral". A properly balanced three-phase system should read 0VAC at this point. BTW, is you yank that rotor out of that motor, you would eventually burn-up the stator if it was not overload protected.


----------



## Mr Rewire (Jan 15, 2011)

BBQ said:


> Rewire, seriously your post makes you look the fool, you know, everyone of us here knows, Brian would clean your clock when it comes to electrical knowledge. To even try to hint otherwise is simply ridiculous.
> 
> You giving Brian a hard time is like Peewee Herman giving Chuck Norris a hard time. :laughing:


 I n the spirit of Peter D
:sleeping::sleeping::sleeping::sleeping:


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## Mr Rewire (Jan 15, 2011)

brian john said:


> I have no problem with engineers or customers specifying NO MWBC. Though is a “GREEN WORLD” it does waste copper.
> 
> The only thing that gets me is some of the excuses I hear, for the specifications requiring MWBC.


 and conduit , but I am to stupid to know that.:laughing:


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## Big John (May 23, 2010)

jmsmith said:


> ...Any kin to it being neutral would be kinda like an intentionally created "floating neutral"....


 I agree, but it sounds like it would work. The only thing is you'd be putting the loads in series with the impedance of the motor windings and vise-versa, so you'd be running at reduced power.

It sounds like a spinning, less efficient version of a zig-zag transformer.

-John


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## jmsmith (Sep 10, 2011)

Big John said:


> I agree, but it sounds like it would work. The only thing is you'd be putting the loads in series with the impedance of the motor windings and vise-versa, so you'd be running at reduced power.
> 
> It sounds like a spinning, less efficient version of a zig-zag transformer.
> 
> -John


It will, John. I just had to wake-up and get my head around what Joe was saying... And yes, you can wire it as a center-grounded delta and create that wild leg! That's what I like about Joe's posts... They get you to thinkin'!
:thumbsup;


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## mdfriday (May 14, 2007)

Mr Rewire said:


> In your senario our techs would inform the person in charge that other circuits would be turned off. If the customer desired an after hours call it would be set up and they would be billed for this call and the after hours call.
> 
> Working hot is stupid and it is hard to fix stupid but I see your point.But the code is looking at safety and handle tied breakers provide a safer install.


No, not a safer INSTALL, a safer, deinstall. The end product is still just as safe when in use.


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## chicken steve (Mar 22, 2011)

I can't quite seem to out my finger on the recent code that i believe states all MWBC's need to be identified comming into a panel this a.m.

maybe one of you code hot shots could help me out?

being that we've piped an entire job out in MWBC's, we've taken the inititave to up the ante' , and tie wrap each MWBC as it enters all the 12x12's (or whatever JB) for the sake of our own sanity

~CS~


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## BBQ (Nov 16, 2010)

The requirement to group is just at the panel



> *210.5 Identification for Branch Circuits.
> 
> (D) Grouping.* The ungrounded and grounded circuit conductors
> of each multiwire branch circuit shall be grouped
> ...


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## joethemechanic (Sep 21, 2011)

Big John said:


> I get where you're going with this, but I can't imagine what that would do to a running motor.



Seems to have no effect. But then again I only ever did it to run a couple of light bulbs

And I hated MacGyver, that show was written for the technically ********.

I spent 10 years of my life dealing with trucks that were cleaned out, stocked and organized by the kind of losers you get out of labor ready or manpower, and kelly staffing. Anything you think you might have on ther truck for that 2 am emergency phone call may or may not be there, and even if it is there, it could be broken. You learn to work around it, especially when you have sewer water coming.


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## joethemechanic (Sep 21, 2011)

And any EE who hates MWBC isn't a real engineer, He never paid his dues working out in the field

He is just some punk that decided with the help of a student guidance councilor that he would make good money being an EE

He is no engineer, he is just a punk that mommy and daddy bought a degree.

Real engineers are born, not created in some half azzed university

To think of all those educational resorses being wasted on a half azzed punk twists me up


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## 480sparky (Sep 20, 2007)

joethemechanic said:


> And any EE who hates MWBC isn't a real engineer, He never paid his dues working out in the field
> 
> He is just some punk that decided with the help of a student guidance councilor that he would make good money being an EE
> 
> ...


I call 'em _suits_. Most of 'em I have no respect for. They have no clue how the real world works.... everything is just ink on paper, produced by the computer they use.


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## BBQ (Nov 16, 2010)

joethemechanic said:


> Real engineers are born, not created in some half azzed university
> 
> To think of all those educational resorses being wasted on a half azzed punk twists me up





480sparky said:


> I call 'em _suits_. Most of 'em I have no respect for. They have no clue how the real world works.... everything is just ink on paper, produced by the computer they use.


I think you are both nuts. :jester:


Certainly some are better than others but damn few could be an engineer without college education. 

There are things you need to know from real life, but there are also things you do need to learn from a book. 

Ken, are all your photography skills self taught or do you read books to supplement your field experience?


----------



## 480sparky (Sep 20, 2007)

BBQ said:


> I think you are both nuts. :jester:
> 
> 
> Certainly some are better than others but damn few could be an engineer without college education.
> ...


Yet, how many EEs actually got dirt under their fingernails working in the field as bona-fide electricians?



BBQ said:


> Ken, are all your photography skills self taught or do you read books to supplement your field experience?


Honestly? 99.5% is self-taught. I'm sure you'll believe that as much as you believe I don't have PhotoShop.


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## brian john (Mar 11, 2007)

My son is in college to be an EE, only one of his professors have any real world experience and that guy worked in robotics.

The do not learn about distribution equipment, the NEC, or anything I would think is real word practical.

I told the story bout my son explaining a bolted pressure switch in class, the professor had no idea what he was talking about. So the googled it and ET was the first hit.

I should add I work with many excellent engineers and have respect for the profession.


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## brian john (Mar 11, 2007)

Double post


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## Cletis (Aug 20, 2010)

*Come on*

Seriously, I can't believe your picking on EE's. I"ve know many. Theory from a book matches up identically to real world problems. There really is no hands on experience needed.


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## BBQ (Nov 16, 2010)

480sparky said:


> Yet, how many EEs actually got dirt under their fingernails working in the field as bona-fide electricians?


Damn few. 

But regardless of that they need to learn the things that can only be learned in a class. 



> Honestly? 99.5% is self-taught.


Really, only 0.5% of what you know about photography has come from a book, or class or instructions?

I can't argue with you about it, only you know the answer. But it sure sounds a bit inflated. 



> I'm sure you'll believe that as much as you believe I don't have PhotoShop.


I do believe you, I have never not believed you don't have that software.

But you still Photoshop images. :thumbsup:


----------



## BBQ (Nov 16, 2010)

Cletis said:


> Seriously, I can't believe your picking on EE's. I"ve know many. Theory from a book matches up identically to real world problems. There really is no hands on experience needed.


:lol::lol:


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## joethemechanic (Sep 21, 2011)

I scored 16.9 on a "Nelson-Denny Reading Test" given to me in the early 90's

Stop with the "you're just a stupid blue collar grunt " bull****.


Phuck those stupid little college boy engineers who didn't grow up working in the field. 

No interest as a kid = Crappy engineer just taking up space and screwing things up.


----------



## knowshorts (Jan 9, 2009)

I have known a few EEs. In person they are were very intelligent and knew their sh¡t. But, they had guys working for them who actually did the work. Guys that probably weren't finished with their education. The EE would glance over it real quick, but due to all he was doing, things were missed. 

Sounds like an exact scenario between a Foreman and an apprentice.


----------



## brian john (Mar 11, 2007)

Cletis said:


> Seriously, I can't believe your picking on EE's. I"ve know many. *Theory from a book matches up identically* to real world problems. There really is no hands on experience needed.


Now you are wrong. College prepares them to work with a firm doing a wide variety of electrical. The work in the construction electrical field is picked up as they work with a firm.

You can read all the books in the world about photography and get the theory down pat, BUT NOTHING will make you a good photographer like getting out there and shooting and shooting and shooting and processing what you have shot.


----------



## BBQ (Nov 16, 2010)

brian john said:


> Now you are wrong.


I think Cletis was being sarcastic, joking and that is why I was laughing after his post.

In my personal opinion ideally EEs would get collage and real world experience.

It ain't going to happen, the kind of person that wants an EE job is not going to take a couple semesters off to work as a helper for $13.00 an hour shagging coffees and doing dirty manual labor.


----------



## BBQ (Nov 16, 2010)

joethemechanic said:


> I scored 16.9 on a "Nelson-Denny Reading Test" given to me in the early 90's


But you are still not quified to be an EE are you? (And neither am I) 



> Stop with the "you're just a stupid blue collar grunt " bull****.


Who said that? 




> Phuck those stupid little college boy engineers who didn't grow up working in the field.


What makes you such an angry guy?



> No interest as a kid = Crappy engineer just taking up space and screwing things up.


Yeah, electricians and mechanics are perfect, they never screw up.


----------



## erics37 (May 7, 2009)

Cletis said:


> I did bid it at that. Are you all seeing engineer's spec'ing this alot nowadays ?? I've talked to 3 now that want no shared neutrals. They all go into how dangerous it is.


Then they better start reengineering virtually every residential service and a majority portion of commercial and industrial services in the country.


----------



## drsparky (Nov 13, 2008)

So who will pay for the huge cost and time of having EE work in the field just to shut a few folks pie holes on chat forums? What field experience would you consider acceptable? Will they follow romex ropers around for a year? Go on the road with the industrial guys? Maybe run MC for a McDonald's?
Required to be a roadie for Cletis' band?


----------



## mattsilkwood (Sep 21, 2008)

My favorite EE to work with will do just that. He'll jump right in the grease with you, I've seen him crawl around and change switches just filthy from head to toe.

Of course, he still makes mistakes from time to time, nobody here can say they don't, but he really understands how his machines work and what it takes to get something done. And there is none of the holier than thou attitude you can get with some of them.


----------



## 220/221 (Sep 25, 2007)

erics37 said:


> Then they better start reengineering virtually every residential service and a majority portion of commercial and industrial services in the country.


With a service, there will only be a couple of failure points and typicaly, no one will be messing with the connections.

With a large commercial building there may be a hundred critical connections that people will be reworking over the years. I know, they SHOULD know better but, eliminating the MWBC's makes the system a bit better. Certainly not idiot proof but it's something. 


And, I don't think the tie bar thing helped anything. Now you have to open the panel and disconnect the circuit if you want to service one of the MWBC legs, or work it hot, or work in the dark


----------



## Cletis (Aug 20, 2010)

*button*



BBQ said:


> I think Cletis was being sarcastic, joking and that is why I was laughing after his post.
> 
> In my personal opinion ideally EEs would get collage and real world experience.
> 
> It ain't going to happen, the kind of person that wants an EE job is not going to take a couple semesters off to work as a helper for $13.00 an hour shagging coffees and doing dirty manual labor.


I still need that sarcastic button. I don't have anything against EE's other than they are treat like *GOD* and we are treated like *DIRT* !!


----------



## 220/221 (Sep 25, 2007)

drsparky said:


> So who will pay for the huge cost and time of having EE work in the field just to shut a few folks pie holes on chat forums?


 
In the long run, it will make money. It's no secret that getting everyone on the same page is productive. I've always held the opinion that EE's should have _some_ kind of hands on experience.


----------



## hardworkingstiff (Jan 22, 2007)

Cletis said:


> I still need that sarcastic button. I don't have anything against EE's other than they are treat like *GOD* and we are treated like *DIRT* !!


You know, I bet it takes a lot of studying and mental work to get an EE degree. Then, a bit more to get the PE to go along with it.

I also bet that not all EE's go around with a better than thou attitude. We tend to just remember the ones that do. I also bet there is a lot of competition in their line of work just like ours and they do not have time to spend with us explaining why they want things done the way they want them done. If we challenge them, they probably get an attitude, sort of like if you have a helper challenging you on your methods at every turn, it get's old and irritating. 

I also bet that EE's sometimes get embarrassed when they mistakenly engineer into the drawings something that is in violation of the NEC. Works fine, but doesn't meet the code then some smart azz EC comes around and rubs his nose in it. 

The majority of engineers I have met are pretty cool people. I guess I've been lucky. I also try to show them the respect they (IMO) have earned by sticking to it and getting their degree and passing the engineering exams. Sure some of them actually believe they are better than the rest of us, but that also holds true of other people, like religious fanatics, a lot of people born into money, and some very intelligent people (although, if you were really that intelligent I think you would know how to not let your attitude show).


----------



## Big John (May 23, 2010)

Well said, _hardworkingstiff__. _It's easy to forget that there's a lot that goes into being an EE, and for all we know they're sitting there thinking "Damn electricians should have to spend more time behind a desk learning engineering!" And when you look at the number of licensed guys who don't understand grounding and bonding... maybe they'd be right. 


brian john said:


> My son is in college to be an EE, only one of his professors have any real world experience and that guy worked in robotics.
> 
> The do not learn about distribution equipment, the NEC, or anything I would think is real word practical....


 If an EE wants to major in power-distribution, there are actually only a few schools in the country where he can.

I've talked to a lot of these guys and they all tell me their courses were based around circuitry and computer design.

It'd be interesting to know how many of EE's end up designing circuits and how many end up working with building and utility power. Sounds like the schools are short-changing these guys.

-John


----------



## brian john (Mar 11, 2007)

BBQ said:


> I think Cletis was being sarcastic, joking and that is why I was laughing after his post.
> 
> In my personal opinion ideally EEs would get collage and real world experience.
> 
> It ain't going to happen, the kind of person that wants an EE job is not going to take a couple semesters off to work as a helper for $13.00 an hour shagging coffees and doing dirty manual labor.


 
I worked with a few that were summer helpers and they had a better respect for their job.


----------



## micromind (Aug 11, 2007)

Sort of off-topic here, but going back a few pages.....

A basic standard 12 lead dual-voltage delta motor has 230 volt windings. When properly connected, 120 is not available.

A basic standard 9 lead dual-voltage wye motor has 133 volt windings. True 120 is not available, but 133 (or thereabouts) is. T1 to T4, T2 to T5, or T3 to T6; your choice. 

If the motor is operated on low voltage, T4, T5, and T6 will be very close to ground, but not exactly at ground. If it's operated at high voltage, these leads will be about 133 higher than ground.

Generally speaking, you can safely extract power from a motor this way provided the load does not exceed about 5% of the high voltage current rating.


----------



## 360max (Jun 10, 2011)

BBQ said:


> Do you have an *ammeter* of some type?
> 
> A qualified person knows to use it before* breaking a connection* in a box like you describe.


..they make clamp on type these days...


----------



## Big John (May 23, 2010)

Rob or Joe, where have you guys actually seen this done? I can't imagine the circumstances where I'd be called on to tie in something like that.

-John


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## BBQ (Nov 16, 2010)

360max said:


> ..they make clamp on type these days...


Yeah that would be the point, what part escaped you?


----------



## erics37 (May 7, 2009)

Big John said:


> Well said, _hardworkingstiff__. _It's easy to forget that there's a lot that goes into being an EE, and for all we know they're sitting there thinking "Damn electricians should have to spend more time behind a desk learning engineering!" And when you look at the number of licensed guys who don't understand grounding and bonding... maybe they'd be right.  If an EE wants to major in power-distribution, there are actually only a few schools in the country where he can.
> 
> I've talked to a lot of these guys and they all tell me their courses were based around circuitry and computer design.
> 
> ...


You're pretty right about that. Here in Oregon, the major universities all offer primarily a "Electrical & Computer Engineering" degree, basically for all the kids that want to create the next big electronic gadget.

The only schools in the state that I've found that offer a focus on Power Transmission & Distribution are Portland State and Oregon Institute of Technology. Neither U of O nor OSU offer s**t.


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## nitro71 (Sep 17, 2009)

I"m betting that tying the disconnecting means together can be traced to the breaker manufactures. From my understanding of the clear as mud requirements any branch circuit that shares neutrals must be handle tied. When you run a full boat on a three phase system you now have to by a three pole breaker unless they make handle ties. They didn't on the last Siemens panel I worked with.


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## micromind (Aug 11, 2007)

Big John said:


> Rob or Joe, where have you guys actually seen this done? I can't imagine the circumstances where I'd be called on to tie in something like that.
> 
> -John


I've seen 120 volt lights on 3ø machine tools. Ones too small to have a control panel, like a bench grinder. In fact, the one in my garage is 208 3ø, and the 120 light on the eyeshield is across T2 and T5.

The oddest one I've seen was a 10HP cut-off saw that used 120 from the motor to energize the starter coil. The starter box was arranged so that the start button wasn't electrical at all, it pushed the contacts closed, The stop button opened the 120 coil circuit. It was pretty old, but came from the factory this way.

I've seen quite a few 240 volt 1ø masonary saws that has 120 volt cooling water pumps that used the motor windings to get the 120.

I've installed pilot lights, hourmeters, and louvers this way.


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## Big John (May 23, 2010)

I'll be damned. What does this do to motor operation? Do you just add the current into the running load of the motor and as long as it doesn't go over FLA you're okay?

-John


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## guest (Feb 21, 2009)

Cletis said:


> Seriously, I can't believe your picking on EE's. I"ve know many. Theory from a book matches up identically to real world problems. There really is no hands on experience needed.





Cletis said:


> I still need that sarcastic button. I don't have anything against EE's other than they are treat like *GOD* and we are treated like *DIRT* !!


Here you go my friend, use these: 

They are the forum's sarcasm smilie. 

So I'll fix that first post for ya: 




Cletis said:


> Seriously, I can't believe your picking on EE's. I"ve know many. Theory from a book matches up identically to real world problems. There really is no hands on experience needed.


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## micromind (Aug 11, 2007)

Big John said:


> I'll be damned. What does this do to motor operation? Do you just add the current into the running load of the motor and as long as it doesn't go over FLA you're okay?
> 
> -John


As long as the external load is small, it has no effect on the motor at all. 

Case in point; a single phase capacitor start dual voltage motor connected for high voltage. 

This motor has 3 windings, all 115 volt. Two run windings and one start winding. The run windings are connected in series for high voltage and the start winding is piggy-backed on one of the run windings. Usually it's T3 and T4. 

Because all 3 windings share the same iron core, the voltage will be fairly constant, regardless of the load. In this case, if you measure voltage during locked-rotor, it's pretty much the same on all 3 windings even though the current through T1 & T2 is way higher. 

An electric motor and a transformer are very similar, the stator is the primary and the rotor is the secondary. As the load increases on the secondary of a transformer, the current will increase in the primary. As the load on the rotor is increased, the current in the stator will increase.


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## 480sparky (Sep 20, 2007)

BBQ said:


> ..........Really, only 0.5% of what you know about photography has come from a book, or class or instructions?
> 
> I can't argue with you about it, only you know the answer. But it sure sounds a bit inflated. .........


How much of your knowledge about electrical comes from books? How many books have you read about bending EMT? Tracing down a short in a circuit? What books tell you how to lay out a cable tray run? Is there a book on how to efficiently trench in lot lights?

Did you really read somewhere in a book that, when troubleshooting a light that doesn't work, it states, "If you turn the switch on, and it doesn't turn on the light, check the lamp. If there's more than one lamp, however, odds are they _all_ aren't burned out, so the issue isn't the lamps."


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## RePhase277 (Feb 5, 2008)

I could see using a motor to pull different control voltages from different windings, like taps in an autotransformer. Never thought of it.


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## BBQ (Nov 16, 2010)

480sparky said:


> How much of your knowledge about electrical comes from books? How many books have you read about bending EMT? Tracing down a short in a circuit? What books tell you how to lay out a cable tray run? Is there a book on how to efficiently trench in lot lights?
> 
> Did you really read somewhere in a book that, when troubleshooting a light that doesn't work, it states, "If you turn the switch on, and it doesn't turn on the light, check the lamp. If there's more than one lamp, however, odds are they _all_ aren't burned out, so the issue isn't the lamps."


You have a point if those types of tasks were all there was to being an electrician. 

I thought we were talking about engineers, not electricians? To me the jobs are vastly different and we can be electricians without college. 


I certainly don't think engineers should be placed on a pedestal but I don't think that they should be generalized as half assed arrogant punks either. :no:


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## RePhase277 (Feb 5, 2008)

480sparky said:


> How much of your knowledge about electrical comes from books? How many books have you read about bending EMT? Tracing down a short in a circuit? What books tell you how to lay out a cable tray run? Is there a book on how to efficiently trench in lot lights?
> 
> Did you really read somewhere in a book that, when troubleshooting a light that doesn't work, it states, "If you turn the switch on, and it doesn't turn on the light, check the lamp. If there's more than one lamp, however, odds are they _all_ aren't burned out, so the issue isn't the lamps."


Well, you see, unless your photography apprentice carries at least a 12B Rating card and has been through the OSHA "Portable Photographic Equipment Handling" course, he is not even allowed to touch a camera. And that's just to tote the device. If you want to actually take a picture, you MUST have at least 10 hours of verifiable class time in Camera Flash PPE. 

Field work is really a small fraction of photographic work.


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## BBQ (Nov 16, 2010)

erics37 said:


> You're pretty right about that. Here in Oregon, the major universities all offer primarily a "Electrical & Computer Engineering" degree, basically for all the kids that want to create the next big electronic gadget.
> 
> The only schools in the state that I've found that offer a focus on Power Transmission & Distribution are Portland State and Oregon Institute of Technology. Neither U of O nor OSU offer s**t.


There are some power engineers that stop by Holt's and I think they said there are only two or three places in the US to get decent power engineering classes. They also said there is a real shortage of power engineers.


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## BBQ (Nov 16, 2010)

InPhase277 said:


> Well, you see, unless your photography apprentice carries at least a 12B Rating card and has been through the OSHA "Portable Photographic Equipment Handling" course, he is not even allowed to touch a camera. And that's just to tote the device. If you want to actually take a picture, you MUST have at least 10 hours of verifiable class time in Camera Flash PPE.
> 
> Field work is really a small fraction of photographic work.


:laughing:


----------



## RePhase277 (Feb 5, 2008)

BBQ said:


> I thought we were talking about engineers, not electricians? To me the jobs are vastly different and we can be electricians without college.


Some of the world's greatest engineers never went to school. And I think you can fully be an "engineer", only better, without college.


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## 480sparky (Sep 20, 2007)

BBQ said:


> You have a point _if those types of tasks were all there was to being an electrician_. ........


That's exactly my point. Thank you.

Do you honestly believe _everything_ there is to know about being an electrician is in a book?


----------



## jmsmith (Sep 10, 2011)

drsparky said:


> So who will pay for the huge cost and time of having EE work in the field just to shut a few folks pie holes on chat forums? What field experience would you consider acceptable? Will they follow romex ropers around for a year? Go on the road with the industrial guys? Maybe run MC for a McDonald's?
> Required to be a roadie for Cletis' band?


When my son told me he wanted to become an EE, I figured it was just his way of getting-back at the old man! I watched him work thru McDonald's during school, at a sawmill during his times off, to his last years working intern at a chemical plant so that he could PAY HIS OWN WAY thru school. This last Oct. he took his PE exam for LA. Not all of them are where they're at because they don't want to do manual labor. As a matter of fact, the older I get, the more I want to work with my head and not my back!!!
:laughing:


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## Cletis (Aug 20, 2010)

*Engineer*

I used to be a S.E.


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## BBQ (Nov 16, 2010)

480sparky said:


> That's exactly my point. Thank you.
> 
> Do you honestly believe _everything_ there is to know about being an electrician is in a book?


No, and I never said it was.

I also have not said that everything I want an engineer to know is in a book either.

But I accept it is not a perfect world and I don't expect things change.


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## BBQ (Nov 16, 2010)

InPhase277 said:


> Some of the world's greatest engineers never went to school. And I think you can fully be an "engineer", only better, without college.


Some, yes, some.

That does not describe most.


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## RePhase277 (Feb 5, 2008)

Cletis said:


> I used to be a S.E.


Sanitation Engineer?


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## cdslotz (Jun 10, 2008)

> And any EE who hates MWBC isn't a real engineer, He never paid his dues working out in the field
> 
> He is just some punk that decided with the help of a student guidance councilor that he would make good money being an EE
> 
> ...


Hahaha
Sounds like some of you guys been busted trying to sub cheap die cast fittings when his spec called for steel.
Or maybe you had to eat $20,000 for taking that cheap "subject to approval" fixture quote.

I tried to become a EE after working many years in the field.
I couldn't cut it.


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## RGH (Sep 12, 2011)

Years ago I work for a military defense contractor for 11yrs. I had to work with ME's and EE's, all day long. They would design the stuff and i had to build it. Some was build to print some was in house design stuff. Some of those guys are still my friends really cool guys some were total aholes with monster egos...some of those nerds could party like madmen and did cool stuff outta work too...others when you showed them an issue would not even talk to ya. Had a Rensselaer EE call me a wire monkey once. Douce bag. When our plant closed 1 helped me get into another plant and he never told me till years later he had recommended me. Some would crawl into the shxt and check issuse others were prettyboys. One dude made his own beer,cool but he played a banjo too lol. Another had this hmmm power smoking machine...


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## 480sparky (Sep 20, 2007)

InPhase277 said:


> Sanitation Engineer?


Smart Electrician. :jester:


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## 480sparky (Sep 20, 2007)

BBQ said:


> ............I thought we were talking about engineers, not electricians? ......



No, we're talking about photographers.


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## micromind (Aug 11, 2007)

The vast majority of EEs I've worked around seemed to be a bit too snobish to be reduced to mere physical work. They wanted to start at the top. 

This attitude is almost always reflected in their drawings as well.

The few who were actual electricians before they were EEs are consistently easier to work with, produce far better drawings, are more than willing to modify their drawings to fit the actual conditions and most importantly, the finished product is far superior to that of an educated idiot.

The company I work for regularly hires recent EE graduates, and puts them to work out in the field. The vast majority of them will go less than a week before the 'I'm too good for this' attitude gets the best of them. 

I honestly believe that the main purpose of college is not to teach students how to be engineers; it it twofold.....

1) To remove any semblance of common sense from the students mind.

2) To instill the largest possible ego........

Once these two are accomplished, you have a fully qualified electrical engineer!

Laugh all you want, we all know how true it actually is.


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## Meadow (Jan 14, 2011)

micromind said:


> The vast majority of EEs I've worked around seemed to be a bit too snobish to be reduced to mere physical work. They wanted to start at the top.
> 
> This attitude is almost always reflected in their drawings as well.
> 
> ...


Im not laughing I see the new guys out of college, They think they can out smart anybody, There drawings look like chicken scratch and they are short tempered when you are honest about a mistake they made.


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## Cgy1 (Nov 27, 2011)

I find the younger the EE, the bigger the Douche bag " I'm better then you "attitude resonates on the surface.


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## 480sparky (Sep 20, 2007)

Sometimes, the guy with the tie gets what's coming to him.


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## Big John (May 23, 2010)

Cgy1 said:


> I find the younger the EE, the bigger the Douche bag " I'm better then you "attitude resonates on the surface.


 Isn't that just the arrogance of youth, though? How many 4th years have you run into who were practically convinced they invented electricity?

-John


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## joethemechanic (Sep 21, 2011)

micromind said:


> 1) To remove any semblance of common sense from the students mind.
> 
> 2) To instill the largest possible ego........
> 
> ...



You ever read John Taylor Gatto?


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## joethemechanic (Sep 21, 2011)

The first lesson I teach is: "Stay in the class where you belong." I don't know who decides that my kids belong there but that's not my business. The children are numbered so that if any get away they can be returned to the right class. Over the years the variety of ways children are numbered has increased dramatically, until it is hard to see the human being under the burden of the numbers each carries. Numbering children is a big and very profitable business, though what the business is designed to accomplish is elusive.

In any case, again, that's not my business. My job is to make the kids like it -- being locked in together, I mean -- or at the minimum, endure it. If things go well, the kids can't imagine themselves anywhere else; they envy and fear the better classes and have contempt for the dumber classes. So the class mostly keeps itself in good marching order. That's the real lesson of any rigged competition like school. You come to know your place.

Nevertheless, in spite of the overall blueprint, I make an effort to urge children to higher levels of test success, promising eventual transfer from the lower-level class as a reward. I insinuate that the day will come when an employer will hire them on the basis of test scores, even though my own experience is that employers are (rightly) indifferent to such things. I never lie outright, but I've come to see that truth and [school]teaching are incompatible.

The lesson of numbered classes is that there is no way out of your class except by magic. Until that happens you must stay where you are put.

The second lesson I teach kids is to turn on and off like a light switch. I demand that they become totally involved in my lessons, jumping up and down in their seats with anticipation, competing vigorously with each other for my favor. But when the bell rings I insist that they drop the work at once and proceed quickly to the next work station. Nothing important is ever finished in my class, nor in any other class I know of.

The lesson of bells is that no work is worth finishing, so why care too deeply about anything? Bells are the secret logic of schooltime; their argument is inexorable; bells destroy past and future, converting every interval into a sameness, as an abstract map makes every living mountain and river the same even though they are not. Bells inoculate each undertaking with indifference.

The third lesson I teach you is to surrender your will to a predestined chain of command. Rights may be granted or withheld, by authority, without appeal. As a schoolteacher I intervene in many personal decisions, issuing a Pass for those I deem legitimate, or initiating a disciplinary confrontation for behavior that threatens my control. My judgments come thick and fast, because individuality is trying constantly to assert itself in my classroom. Individuality is a curse to all systems of classification, a contradiction of class theory.

Here are some common ways it shows up: children sneak away for a private moment in the toilet on the pretext of moving their bowels; they trick me out of a private instant in the hallway on the grounds that they need water. Sometimes free will appears right in front of me in children angry, depressed or exhilarated by things outside my ken. Rights in such things cannot exist for schoolteachers; only privileges, which can be withdrawn, exist.

The fourth lesson I teach is that only I determine what curriculum you will study. (Rather, I enforce decisions transmitted by the people who pay me). This power lets me separate good kids from bad kids instantly. Good kids do the tasks I appoint with a minimum of conflict and a decent show of enthusiasm. Of the millions of things of value to learn, I decide what few we have time for. The choices are mine. Curiosity has no important place in my work, only conformity.

Bad kids fight against this, of course, trying openly or covertly to make decisions for themselves about what they will learn. How can we allow that and survive as schoolteachers? Fortunately there are procedures to break the will of those who resist.

This is another way I teach the lesson of dependency. Good people wait for a teacher to tell them what to do. This is the most important lesson of all, that we must wait for other people, better trained than ourselves, to make the meanings of our lives. It is no exaggeration to say that our entire economy depends upon this lesson being learned. Think of what would fall apart if kids weren't trained in the dependency lesson: The social-service businesses could hardly survive, including the fast-growing counseling industry; commercial entertainment of all sorts, along with television, would wither if people remembered how to make their own fun; the food services, restaurants and prepared-food warehouses would shrink if people returned to making their own meals rather than depending on strangers to cook for them. Much of modern law, medicine, and engineering would go too -- the clothing business as well -- unless a guaranteed supply of helpless people poured out of our schools each year. We've built a way of life that depends on people doing what they are told because they don't know any other way. For God's sake, let's not rock that boat!

In lesson five I teach that your self-respect should depend on an observer's measure of your worth. My kids are constantly evaluated and judged. A monthly report, impressive in its precision, is sent into students' homes to spread approval or to mark exactly -- down to a single percentage point -- how dissatisfied with their children parents should be. Although some people might be surprised how little time or reflection goes into making up these records, the cumulative weight of the objective- seeming documents establishes a profile of defect which compels a child to arrive at a certain decisions about himself and his future based on the casual judgment of strangers.

Self-evaluation -- the staple of every major philosophical system that ever appeared on the planet -- is never a factor in these things. The lesson of report cards, grades, and tests is that children should not trust themselves or their parents, but must rely on the evaluation of certified officials. People need to be told what they are worth.

In lesson six I teach children that they are being watched. I keep each student under constant surveillance and so do my colleagues. There are no private spaces for children; there is no private time. Class change lasts 300 seconds to keep promiscuous fraternization at low levels. Students are encouraged to tattle on each other, even to tattle on their parents. Of course I encourage parents to file their own child's waywardness, too.

I assign "homework" so that this surveillance extends into the household, where students might otherwise use the time to learn something unauthorized, perhaps from a father or mother, or by apprenticing to some wiser person in the neighborhood.

The lesson of constant surveillance is that no one can be trusted, that privacy is not legitimate. Surveillance is an ancient urgency among certain influential thinkers; it was a central prescription set down by Calvin in the Institutes, by Plato in the Republic, by Hobbes, by Comte, by Francis Bacon. All these childless men discovered the same thing: Children must be closely watched if you want to keep a society under central control.


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## joethemechanic (Sep 21, 2011)

cdslotz said:


> Hahaha
> Sounds like some of you guys been busted trying to sub cheap die cast fittings when his spec called for steel.
> Or maybe you had to eat $20,000 for taking that cheap "subject to approval" fixture quote.
> 
> ...



You're way off base here. Because most of my dealings with engineers over the years have been on a lateral level or with me as their immediate supervisor. The last time I worked as an employee for anyone I was VP of a small company that provided engineering and millwright services. In fact I always had at least an equal say about the designs, and in the later part of my career almost without exception if it didn't get my approval, it was a no-go


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## chicken steve (Mar 22, 2011)

Joe,

with lessons like that 

i think you might end up with dudes like these>


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## Meadow (Jan 14, 2011)

joethemechanic said:


> The first lesson I teach is: "Stay in the class where you belong." I don't know who decides that my kids belong there but that's not my business. The children are numbered so that if any get away they can be returned to the right class. Over the years the variety of ways children are numbered has increased dramatically, until it is hard to see the human being under the burden of the numbers each carries. Numbering children is a big and very profitable business, though what the business is designed to accomplish is elusive.
> 
> In any case, again, that's not my business. My job is to make the kids like it -- being locked in together, I mean -- or at the minimum, endure it. If things go well, the kids can't imagine themselves anywhere else; they envy and fear the better classes and have contempt for the dumber classes. So the class mostly keeps itself in good marching order. That's the real lesson of any rigged competition like school. You come to know your place.
> 
> ...


I take it school was a bad experience for you?:laughing: Seriously you are lucky that your no longer in school and your worst fear was bells. Todays students are abused more by each other than by the teachers. Students these days spend class time bullying each other and talking about where they can find the best shrooms. Schools themselves are not so much the problem as parents who just dont care how there kids turn out. In turn these out of control kids bring down there schools and the rest of society. 
"The third lesson I teach you is to surrender your will to a predestined chain of command. Rights may be granted or withheld, by authority, without appeal.":lol:It used to be that way, there are actually many and a growing number of teachers afraid of the students.:no:


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## Cgy1 (Nov 27, 2011)

Big John said:


> Isn't that just the arrogance of youth, though? How many 4th years have you run into who were practically convinced they invented electricity?
> 
> -John


Yes and no. I feel the younger people today (which includes me since I'm still in my 20's) have been brought up in a way that many think they are entitled to everything and anything. Their "high school" mentality has carried over into adulthood for many young professionals today. I knew a guy who took engineering in university because he thought it would get him"*****". 

Hahaha defiantly know what you're saying about the 4th year who thinks he is the show. Walking around exerting his superiority over apprentices of lesser years then him, and only friendly with guys/gals who are journeyman


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## joethemechanic (Sep 21, 2011)

John Taylor Gatto said:


> The lesson of constant surveillance is that no one can be trusted, that privacy is not legitimate. Surveillance is an ancient urgency among certain influential thinkers; it was a central prescription set down by Calvin in the Institutes, by Plato in the Republic, by Hobbes, by Comte, by _Francis Bacon_. All these childless men discovered the same thing: Children must be closely watched if you want to keep a society under central control.





meadow said:


> I take it school was a bad experience for you?:laughing: Seriously you are lucky that your no longer in school and your worst fear was bells. Todays students are abused more by each other than by the teachers. Students these days spend class time bullying each other and talking about where they can find the best shrooms. Schools themselves are not so much the problem as parents who just dont care how there kids turn out. In turn these out of control kids bring down there schools and the rest of society.
> "The third lesson I teach you is to surrender your will to a predestined chain of command. Rights may be granted or withheld, by authority, without appeal.":lol:It used to be that way, there are actually many and a growing number of teachers afraid of the students.:no:


I was my first grade teacher's pet. Miss Grady was a fiftyish never married, no children woman. I'm Irish and Pa German, (I looked like I could have been of her own blood) and I went to school already knowing how to read, and read well.

She taught me that number systems did not have to be 10 based. Opening up the concept of things like hex to me.

In second grade I flunked math.


The scary thing is I attended Bensalem Public Schools.

_New Atlantis_ is a utopian novel _by Sir Francis Bacon_, published in Latin (as Nova Atlantis) in 1624 and in English in 1627. In this work, Bacon portrayed a vision of the future of human discovery and knowledge, expressing his aspirations and ideals for humankind. The novel depicts the creation of a utopian land where "generosity and enlightenment, dignity and splendour, piety and public spirit" are the commonly held qualities of the inhabitants of _"Bensalem"_. The plan and organization of his ideal college, "Salomon's House" (or Solomon's House) envisioned the modern research university in both applied and pure sciences.


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## micromind (Aug 11, 2007)

joethemechanic said:


> You ever read John Taylor Gatto?


No, but I get the idea that I should.......


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## guest (Feb 21, 2009)

And WTF does any of this have to do with MWBC's? 

This was a good thread that has now gone Kablower.


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## Jlarson (Jun 28, 2009)

:blink::blink::blink::blink:

what the hell


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## joethemechanic (Sep 21, 2011)

mxslick said:


> And WTF does any of this have to do with MWBC's?



Eliminating MWBCs is a symptom of the dumbing down of America

http://en.wikipedia.org/wiki/Dumbing_Us_Down

"The Public School Nightmare: Why fix a system designed to destroy individual thought?" 

http://www.diablovalleyschool.org/nightmare.shtml


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## JmanAllen (Aug 3, 2011)

micromind said:


> In my opinion, if you lack the ability to handle a MWBC, you have no place in the electrical trade.


Couldn't agree more. Seems like all new codes are to push a product or make it easier for the local handyman to work on

Sent from my iPhone using ET Forum


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## joethemechanic (Sep 21, 2011)

MWBCs are very elegant from an engineering standpoint. Kinda like things with 3 legs, tripods, three phase power,,,,,,,,,,,,,

They work so well that here in North America almost without exception residential transformers are connected to feed a MWBC, and almost everyone's home is served by a MWBC.

As soon as you go over 50% you start decreasing load on a conductor, _and_ that first 50 doesn't necessarily have to be loading N in the first place.

To me, that is an elegant design


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## Peerless Design (Dec 3, 2011)

I don’t know any EEs specifying dedicated neutrals for all of their general purpose circuits. This guy doesn’t know what he’s talking about. He doesn’t even know the difference between “basis of design” and “bases of design”.

Using shared neutrals is better than dedicated neutrals. I once had a call to a business that kept burning up components. They had someone tell them they had to oversize the neutrals, and use dedicated neutrals, but the problem persisted. They were extremely hesitant to let me remove all the dedicated neutrals until I explained that the three circuits drew the same amount, and that the neutral carried nothing. Each circuit conductor dissipated heat. If you remove the dedicated neutrals you remove three of those heaters going all the way back to the panel. I removed the dedicated neutrals, and showed them that the remaining common neutral was not carrying any current. Problem solved.


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## joethemechanic (Sep 21, 2011)

Peerless Design said:


> I don’t know any EEs specifying dedicated neutrals for all of their general purpose circuits. This guy doesn’t know what he’s talking about. He doesn’t even know the difference between “basis of design” and “bases of design”.
> 
> Using shared neutrals is better than dedicated neutrals. I once had a call to a business that kept burning up components. They had someone tell them they had to oversize the neutrals, and use dedicated neutrals, but the problem persisted. They were extremely hesitant to let me remove all the dedicated neutrals until I explained that the three circuits drew the same amount, and that the neutral carried nothing. Each circuit conductor dissipated heat. If you remove the dedicated neutrals you remove three of those heaters going all the way back to the panel. I removed the dedicated neutrals, and showed them that the remaining common neutral was not carrying any current. Problem solved.


Really, who in their right mind thinks making a circuit longer than necessary is a "good thing"?

Question though, if somebody runs 3 neutrals out with his 3 phases of hots, and you tie the three together (to reduce the heating) _at or near the load end_, is it a code violation?


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## micromind (Aug 11, 2007)

joethemechanic said:


> Really, who in their right mind thinks making a circuit longer than necessary is a "good thing"?
> 
> Question though, if somebody runs 3 neutrals out with his 3 phases of hots, and you tie the three together (to reduce the heating) _at or near the load end_, is it a code violation?


If they are smaller than 1/0, it would be a violation of 310.4


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## user8640521 (Jan 17, 2009)

Mr Rewire said:


> A hack wouldn't use a handle tied breaker.The point is in the real world just looking in the jbox you cannot identlfy which wire goes to which neutral or if that neutral is even on a MWBC. I dont see how requiring MWBC to be handle tied is a bad idea .


deep cleansing breath.... pause.... ok. light blowtorch and begin flaming.

i'm in a food packing plant, standing in a puddle of soapy water, working
on a scale. and 'cause i'm not an idiot, i would like to be able to shut this thing
off, so i clip on my circuit tracer, and find out what breaker it's on.

yep. there it is. the middle leg of a three pole breaker feeding three separate
loads, one of which is the power for the infeed conveyor to the blancher.

that can't be shut off on peril of death. cause the whole process line is
running over it.

but the scale is down, and that means the metal detector right next to
the scale is down also, and that means an unsafe production situation
exists.

and a hazardous working situation exists as well, cause if i down that 
conveyor, my work is in mortal peril. i'll never be given work in that plant
again.

so, as i stand there in a puddle of soapy water, working something hot
that didn't need to be worked hot, 'cause there is $100k of product
in process that can't be stopped.....

i'll take great comfort in knowing that you feel it's much better this way.

you do actually work on stuff, don't you?


pfffft.


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## tim lutton (Jan 3, 2012)

I'm not sure sharing neutrals is "deadly' but I'v been running new neutrals for MWBC and even oversizing neutrals for 25 years due to the computor load.


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## Dennis Alwon (May 9, 2009)

tim lutton said:


> I'm not sure sharing neutrals is "deadly' but I'v been running new neutrals for MWBC and even oversizing neutrals for 25 years due to the computor load.



The problem with mwbc is if the neutral gets compromised then you will have 240V going into one circuit and blowing things up. I have seen it many times esp. on services to residence. Poco looses a neutral or it's degraded then the power in the house will vary voltage-- common scene is phase one to ground 60V and phase 2 to ground 180V-- sum is still 240V. Now ths will usually need a load to see it's ugly face -- under no load you will usually get normal readings unless he neutral is totally shot.


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