# Generator line and low voltage in the same conduit??



## micromind (Aug 11, 2007)

All conductors in a raceway must be rated for the highest voltage in said raceway. 

So no, thermostat wire wouldn't be allowed unless it is rated for the highest voltage present in the conduit.


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## Elephante (Nov 16, 2011)

micromind said:


> All conductors in a raceway must be rated for the highest voltage in said raceway.
> 
> So no, thermostat wire wouldn't be allowed unless it is rated for the highest voltage present in the conduit.


So you can't mix class 1 , 2 , or 3 together pretty much?


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## MTW (Aug 28, 2013)

Elephante said:


> So you can't mix class 1 , 2 , or 3 together pretty much?


Negative, unless you reclassify the entire low voltage circuit as line voltage. That would mean you would have to wire the entire low voltage circuit with "line voltage" methods - no t-stat wire, open splices, etc.


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## B4T (Feb 10, 2009)

Generac allows you to run control and power conductors in same conduit...

But the control wires must be rated 600V.. I use (6) rolls of #18 THHN for that....


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## Elephante (Nov 16, 2011)

B4T said:


> Generac allows you to run control and power conductors in same conduit...
> 
> But the control wires must be rated 600V.. I use (6) rolls of #18 THHN for that....


What about the load shed do you Ty wrap? I hate Ty wrapping onto conduit.


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## B4T (Feb 10, 2009)

Elephante said:


> What about the load shed do you Ty wrap? I hate Ty wrapping onto conduit.


Yes... I use wire ties... anything looks better than bell wire swinging in the breeze...


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## flyboy (Jun 13, 2011)

B4T said:


> Generac allows you to run control and power conductors in same conduit...
> 
> But the control wires must be rated 600V.. I use (6) rolls of #18 THHN for that....


Not on the liquid cools...:no:


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## flyboy (Jun 13, 2011)

Elephante said:


> So you can't mix class 1 , 2 , or 3 together pretty much?


You should read Article 725 of the NEC for a complete understanding of what you can and can't do. :thumbsup:


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## 360max (Jun 10, 2011)

B4T said:


> Generac allows you to run control and power conductors in same conduit...
> 
> But the control wires must be rated 600V.. I use (6) rolls of #18 *THHN* for that....


indoor generator? :whistling2:


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## BBQ (Nov 16, 2010)

Elephante said:


> Can I install thermostat wire with the feeders that go to a generator? Class 2 thermostat wire.....I have never done it this way. Is it wrong running the two? It says class 2 is limited to 150 volts in chapter 9. Do the classes have to be the same?


There is no yes or no answer to this question, there are a ton of variables to it.

There is the insulation voltage rating, there is the restrictions of class 2 and class 3 circuits with power wiring, but in some instances they can be reclassified to class 1 which can be run with power wiring. 

There are the manufacturers instructions, there are also reliability issues if the control circuit is a data link. Even if you could run it together it would be a bad idea. 

We just always keep them separate, it is easy to do and eliminates questions.


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## BBQ (Nov 16, 2010)

B4T said:


> Generac allows you to run control and power conductors in same conduit...
> 
> But the control wires must be rated 600V.. I use (6) rolls of #18 THHN for that....


And they all have to be a chapter 3 wiring method from ATS to generator. No switching to thermostat wire inside the building.


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## Southeast Power (Jan 18, 2009)

They make a cable, almost looks like romex, just for 2 wire control for AC units that can be pulled into power conduit.
We use it for retrofits in jurisdictions where the inspector enforces the class 2 section.
Otherwise, it is just keeping the THHN that the original contractor installed.


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## HackWork (Oct 2, 2009)

I've always ran the power and control wires for the generator in the same conduit but kept the bell wire to shed the AC completely separate.


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## BBQ (Nov 16, 2010)

HackWork said:


> I've always ran the power and control wires for the generator in the same conduit


Interesting but says nothing about if it was code compliant or not.

It could be either.


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## HackWork (Oct 2, 2009)

BBQ said:


> Interesting but says nothing about if it was code compliant or not.
> 
> It could be either.


Why isn't it code compliant?


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## Elephante (Nov 16, 2011)

Is there a list of what types of wire are class circuits. Thhn would be class 1 correct? I am reading 725 now this whole section is lil confusing.


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## Big John (May 23, 2010)

Elephante said:


> Is there a list of what types of wire are class circuits. Thhn would be class 1 correct? I am reading 725 now this whole section is lil confusing.


 725.46 

Basically they need to be a "Article 300" wiring method, whereas Class 2 and Class 3 cables are going to be dedicated use and listed as such.


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## Elephante (Nov 16, 2011)

This might be a little off topic but are we allowed to Ty wrap class 2 or class 3 onto conduit? It looks like 725.143 says no.


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## BBQ (Nov 16, 2010)

Elephante said:


> Is there a list of what types of wire are class circuits. Thhn would be class 1 correct? I am reading 725 now this whole section is lil confusing.


The class of the circuit is determined by the source of the power not the type of wire you use.


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## Big John (May 23, 2010)

Elephante said:


> This might be a little off topic but are we allowed to Ty wrap class 2 or class 3 onto conduit? It looks like 725.143 says no.


 It's legal sometimes. Check out 300.11(B)(2).


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## Elephante (Nov 16, 2011)

BBQ said:


> The class of the circuit is determined by the source of the power not the type of wire you use.


Gotcha.. Thanks.i was getting confused on that.


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## B4T (Feb 10, 2009)

flyboy said:


> Not on the liquid cools...:no:


I have never installed a liquid cool.. too much work and I only do installs I can do by myself..


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## BBQ (Nov 16, 2010)

B4T said:


> I have never installed a liquid cool.. too much work and I only do installs I can do by myself..


How is it more work? :blink:


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## Elephante (Nov 16, 2011)

BBQ said:


> The class of the circuit is determined by the source of the power not the type of wire you use.


I am looking at thermostat wire on the southwire website and they have it labeled class 2 wire? There is no source power when its on a reel. Why did they label it class 2 then?


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## Big John (May 23, 2010)

Elephante said:


> I am looking at thermostat wire on the southwire website and they have it labeled class 2 wire? There is no source power when its on a reel. Why did they label it class 2 then?


 Because a Class 2 supply means that you have a lot more freedom with how you want to wire the circuit, but if you do that then one of the restrictions is that it must be within cables designated for Class 2 use.

Short answer: The wiring method needs to match the power supply.


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## B4T (Feb 10, 2009)

BBQ said:


> How is it more work? :blink:


Concrete pad and having to get a crane involved with getting the generator delivered and placed on the pad...


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## BBQ (Nov 16, 2010)

Elephante said:


> I am looking at thermostat wire on the southwire website and they have it labeled class 2 wire? There is no source power when its on a reel. Why did they label it class 2 then?


It is telling you it is OK for class 2 or class 3 but not class 1 or power circuits.

Now you need to know if the power source that would power this wire is class 1, 2 or 3.

That depends on the Va the source is capable of supplying. 

In other words any system labeled Class 2 is power limited, so much so it is considered safe. It can't give a lethal shock and it can't start a fire.


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## B4T (Feb 10, 2009)

I tried working with a rigging company to have the generator delivered to their place of business...

But they didn't want to get involved with looking for damage and signing the delivery ticket...


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## BBQ (Nov 16, 2010)

B4T said:


> I tried working with a rigging company to have the generator delivered to their place of business...
> 
> But they didn't want to get involved with looking for damage and signing the delivery ticket...


That is pretty odd as that is standard practice for us.


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## B4T (Feb 10, 2009)

BBQ said:


> That is pretty odd as that is standard practice for us.


All about money.. I might sell a liquid cooled unit once every (2) years...

Look at the amount of units and other things a crane is needed for that generates $$$$ for them....


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## MTW (Aug 28, 2013)

BBQ said:


> And they all have to be a chapter 3 wiring method from ATS to generator. No switching to thermostat wire inside the building.


I already said that. :blink:


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## BBQ (Nov 16, 2010)

MTW said:


> I already said that. :blink:


It does not count until I say it.

You must know that by now. :laughing:


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## MTW (Aug 28, 2013)

BBQ said:


> It does not count until I say it.
> 
> You must know that by now. :laughing:


Well people do say you're arrogant. :whistling2:


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## BBQ (Nov 16, 2010)

MTW said:


> Well people do say you're arrogant. :whistling2:


No ......... :no:


BTW I was with DS most of yesterday, he may have mentioned it. :laughing:


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## MTW (Aug 28, 2013)

BBQ said:


> No ......... :no:
> 
> 
> BTW I was with DS most of yesterday, he may have mentioned it. :laughing:



I can hear him saying it it my head. :laughing:

Was he sidejobbing in Fall Reev again?


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## 123electric (Jun 3, 2012)

Figured I'd ask at this existing thread.

Have a customer that we did a 48 kw generator for that runs on natural gas. Problem is according to gas company we can put his house in gas starve mode. 
What I did to compensate is drop out the least most important gas item (pool heater 250k btu) the moment the generator started using a 120 volt transformer to 24 volt. At his pool house installed a 40 amp NC relay with 24 coil that opened when generator was running. Problem is its a 1800 rpm generator that at cool down and start up mode drops to 1200 rpm thus dropping my transformer voltage and allowing pool panel to run. 
Thought of using the two wire start to power a 12volt Dc relay then dry contacts.
Also need pool heater dropped also during generator exercise mode. Also thought of using my existing LCM I have there. Possible a set of contacts, but I believe that only for load she'd while under load....


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## flyboy (Jun 13, 2011)

B4T said:


> I have never installed a liquid cool.. too much work and I only do installs I can do by myself..


I don't blame you, it would be a lot work for one guy. :thumbsup:


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## 123electric (Jun 3, 2012)

Anybody dare take a shot at my last post??


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## McClary’s Electrical (Feb 21, 2009)

B4T said:


> All about money.. I might sell a liquid cooled unit once every (2) years...
> 
> Look at the amount of units and other things a crane is needed for that generates $$$$ for them....


We just did a 45 kw with no crane and no machinery.


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## HackWork (Oct 2, 2009)

mcclary's electrical said:


> We just did a 45 kw with no crane and no machinery.


Because you are so awesome.


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## 123electric (Jun 3, 2012)

Still no one wants to touch my post??


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## Pete m. (Nov 19, 2011)

123electric said:


> Anybody dare take a shot at my last post??


Can the gas supplier raise the delivery pressure and utilize regulators at the appliances? That is commonplace here when a generator is added and the existing gas supply can't handle the demand.

Pete


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## 123electric (Jun 3, 2012)

They raised it already to compensate for his 1800 foot long driveway. Changes the gas meter to a commercial rotary gas meter and misseled a 2" yellow gas to the generator from the meter


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## 123electric (Jun 3, 2012)

I dought anyone will have an answer for my complex issue.


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## Service Call (Jul 9, 2011)

123electric said:


> I dought anyone will have an answer for my complex issue.


How about a contactor with time delay on make, say 5-10 mins delay.


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## 123electric (Jun 3, 2012)

Lol, question is were do we grab the NO or NC 
Dry contacts from.


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## 123electric (Jun 3, 2012)

Also the time delay relay were to place it in cntrl loop


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## Service Call (Jul 9, 2011)

How about installing it right at the heater. 10 min delay on make should clear up it wanting to start while the genny cools down.


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## flyboy (Jun 13, 2011)

mcclary's electrical said:


> We just did a 45 kw with no crane and no machinery.


We don't need no stinking crane.:jester: 

We put the liquid cools in the back of a little 12 foot trainer on top of 4 pieces of 3/4 or 1 inch pipe, strap it down and roll that baby off the trailer and right onto the concrete pad. 

We do have a fork lift at the shop to load it in the trailer, but we don't take the fork lift to the job site.


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## McClary’s Electrical (Feb 21, 2009)

flyboy said:


> We don't need no stinking crane.:jester:
> 
> We put the liquid cools in the back of a little 12 foot trainer on top of 4 pieces of 3/4 or 1 inch pipe, strap it down and roll that baby off the trailer and right onto the concrete pad.
> 
> We do have a fork lift at the shop to load it in the trailer, but we don't take the fork lift to the job site.


That is EXACTLY what we did.


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## HackWork (Oct 2, 2009)

Why not just use a helicopter.

Generac should do that, full delivery from their manufacturing plant to the pad in one shot. 

You know how many times each generator is probably moved before it gets to it's final destination?


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## Going_Commando (Oct 1, 2011)

123electric said:


> Figured I'd ask at this existing thread.
> 
> Have a customer that we did a 48 kw generator for that runs on natural gas. Problem is according to gas company we can put his house in gas starve mode.
> What I did to compensate is drop out the least most important gas item (pool heater 250k btu) the moment the generator started using a 120 volt transformer to 24 volt. At his pool house installed a 40 amp NC relay with 24 coil that opened when generator was running. Problem is its a 1800 rpm generator that at cool down and start up mode drops to 1200 rpm thus dropping my transformer voltage and allowing pool panel to run.
> ...


Put a flow switch on the gas line coming in to the generator. That way when the generator starts drawing fuel, that will close the circuit to your contractor and kick off the pool heater.


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## 123electric (Jun 3, 2012)

Going_Commando said:


> Put a flow switch on the gas line coming in to the generator. That way when the generator starts drawing fuel, that will close the circuit to your contractor and kick off the pool heater.


Wow! I like that idea. It will be my next step if my two wire start contacts idea will not work (terminals 3&4) 

Picked up a relay that has a coil voltage range between 10 to 30 volts DC. At my ats measured the voltage of terminal 4 to ground and I get 12 volts. After dropping utility power the other terminal receives 12 volts terminal 3. I was going to use one side to power my coil and ground. Then pass 24 volts from a transformer i installed in the ats pass the power through a set of NO contact on the relay, to then power the 24 volt coil at my NC controlling the power to the pool panel being that I can't get to the pool heater.


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## 123electric (Jun 3, 2012)

Met to say NC relay for my previous post (in the last sentence)


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## Ephriam (Sep 17, 2013)

Given that the control circuit is a data link, will using a separate PVC conduit that lies in close proximity to the power line PVC conduit provide enough isolation to prevent crosstalk? Must use at least one metal conduit?


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## Magnettica (Jan 23, 2007)

Not reading the whole thread....


With Generac you're able to run these lines all in the same conduit. Kholer, not so much.


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## B4T (Feb 10, 2009)

Ephriam said:


> Given that the control circuit is a data link, will using a separate PVC conduit that lies in close proximity to the power line PVC conduit provide enough isolation to prevent crosstalk? Must use at least one metal conduit?


You need to check the "Installers Guide' that comes with the generator to get the right answer.. 

If you don't have a generator yet.. call Tech Support..


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