# Racking in breakers



## vos (Apr 1, 2010)

sorry.... what's racking a breaker?


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## MDShunk (Jan 7, 2007)

nitro71 said:


> I haven't had much opportunity to be about big switch gear so have some questions.
> 
> What constitutes a hazard when racking a breaker in? Is there a voltage, amperage size where it becomes a hazard? What types of breakers require racking versus just turning them on. As you tell I'm foggy about this. Want to know how to identify that there is a hazard and have an idea of what to do about it.


What constitutes a hazard when racking a breaker in, you ask? In 2011, I'd say that the simple act of racking in a breaker is the hazardous act, in and of itself. Parts break. Parts don't line up. Things malfunction. Even in the best PPE made, you're still going to get hurt in some way if things go badly. I think the three or four companies that offer remote controlled racking solutions are on the right track.


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## MDShunk (Jan 7, 2007)

vos said:


> sorry.... what's racking a breaker?


Sticking it in the rack.


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## nitro71 (Sep 17, 2009)

MDShunk said:


> Sticking it in the rack.


Shoot MD, I guess I didn't understand that. So it is "changing" out a breaker? I had thought it refered to opening and closing the breaker.


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## MDShunk (Jan 7, 2007)

nitro71 said:


> Shoot MD, I guess I didn't understand that. So it is "changing" out a breaker? I had thought it refered to opening and closing the breaker.


Uh... no. We're talking about breakers that weigh hundreds and hundreds of pounds.


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## nitro71 (Sep 17, 2009)

Can you define racking in a breaker for me? I'm kinda confused now.


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## Edrick (Jun 6, 2010)

I was always under the impression it was in high voltage scenarios where you basically have the enclosed cabinet in the switching gear where you "pump" and the breaker slowly with every movement goes into place.


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## vos (Apr 1, 2010)

Thanks used you tube but thanks any way


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## MDShunk (Jan 7, 2007)

nitro71 said:


> Can you define racking in a breaker for me? I'm kinda confused now.


Watch this video: http://www.cbsarcsafe.com/videos/video-remote-racking-of-GE-PowerVac-RRS-1-with-camera-and-light.wmv


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## nitro71 (Sep 17, 2009)

Edrick said:


> I was always under the impression it was in high voltage scenarios where you basically have the enclosed cabinet in the switching gear where you "pump" and the breaker slowly with every movement goes into place.


That was my assumption. I haven't had the oppurtunity to work on this type of gear yet so..


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## Jlarson (Jun 28, 2009)

Basically, chit happens. And its almost never good for the guy standing or kneeling there cranking on the thing or whatever. 


Best and really the only safe way to do it is with remote racking gear IMO.


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## nitro71 (Sep 17, 2009)

MDShunk said:


> Watch this video: http://www.cbsarcsafe.com/videos/video-remote-racking-of-GE-PowerVac-RRS-1-with-camera-and-light.wmv


Watching


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## nitro71 (Sep 17, 2009)

I watched it and it's removing and installing large switchgear. Now I can understand why there would be a hazard while doing live. So instead of calling it installing and removing they call it racking. Got it.


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## MDShunk (Jan 7, 2007)

nitro71 said:


> I watched it and it's removing and installing large switchgear. Now I can understand why there would be a hazard while doing live. So instead of calling it installing and removing they call it racking. Got it.


Ten-four. Some go so far as to call turning on or off large frame breakers as "racking", but that's not really the case. If it makes you feel good to say that, fine, but don't be surprised if someone gives you a puzzled look.


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## nitro71 (Sep 17, 2009)

Thanks for straightening me out!


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## Big John (May 23, 2010)

Always rack remotely or on a dead bus. When racking goes wrong...




-John


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## Edrick (Jun 6, 2010)

What happened to the guy do you know?


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## brother (Nov 25, 2008)

duplicate.


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## lefleuron (May 22, 2010)

Edrick said:


> What happened to the guy do you know?


 Far as I remember, he was killed. I think the helper was a female, and she was burned pretty badly.

I also seam to remember he racked the wrong breaker here. the one above had no load on it- but the one he pulled was under full load.


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## drsparky (Nov 13, 2008)

Remote racking is the best way to go. There are some vertical lift ie: General Electric Magneblast and Allis-Chalmers HF that you still have to manually rack.
Even smaller stacked breakers have remote racking equipment available.


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## ecelectric (Mar 27, 2009)

I work for a local utility and when we rack in or out our breakers have a motor that locks in with a hundred foot cord on it to operate.but in some of our older stations the control handle for the breaker is right in front of it so if this is the case we would wear the appropriate calorie arc suit for the fault duty of that station.all the newer stations we have they have the control handles in another room


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## ScooterMcGavin (Jan 24, 2011)

I work in a power plant. All the breakers have to be manually racked in and out. A few years a go while an operator was racking a breaker in it blew up in his face. They never determined the exact cause of the fault, but they suspect that there was a rat in the cubicle because of all the rat crap at the bottom of the switch gear. Arc flash suits weren't required at the time either.

Now we have arc flash relays that we cut in while performing racking operations. It raises the sensisitivty of the over current relays and it supposed to pick up a fault within just a few cycles. Only problem is if you forget to cut it out when done and start a pump it will trip the unit.


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## MDShunk (Jan 7, 2007)

People are under the mistaken impression that arc flash suits are going to save them. Get this straight: You're still going to get hurt. Just maybe not dead.

Sent from my iPhone using the ElectricianTalk Forum app. Please excuse my brevity.


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## danickstr (Mar 21, 2010)

so...to answer the OP question...


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## MDShunk (Jan 7, 2007)

danickstr said:


> so...to answer the OP question...


Who cares?

Sent from my iPhone using the ElectricianTalk Forum app. Please excuse my brevity.


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## danickstr (Mar 21, 2010)

:thumbup:


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## Zog (Apr 15, 2009)

drsparky said:


> Remote racking is the best way to go. There are some vertical lift ie: General Electric Magneblast and Allis-Chalmers HF that you still have to manually rack.
> Even smaller stacked breakers have remote racking equipment available.


Remote racking is available for vertical lift breaker too.


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## Zog (Apr 15, 2009)

nitro71 said:


> I haven't had much opportunity to be about big switch gear so have some questions.
> 
> What constitutes a hazard when racking a breaker in? Is there a voltage, amperage size where it becomes a hazard? What types of breakers require racking versus just turning them on. As you tell I'm foggy about this. Want to know how to identify that there is a hazard and have an idea of what to do about it.


Racking breakers is considered one of the highest risk tasks by the 70E commitee. They changed the tables in 2009 so all racking operations, regardless of voltage or if the doors are open or closed require HRC 4 PPE, assuming you can use the tables at your facility. 

Nealy every utility in the US has gone to remote racking, many industrial facilities are following suit. It is quickly becoming the norm to use remote devices to rack breakers.


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## mattsilkwood (Sep 21, 2008)

MDShunk said:


> People are under the mistaken impression that arc flash suits are going to save them. Get this straight: You're still going to get hurt. Just maybe not dead.
> 
> Sent from my iPhone using the ElectricianTalk Forum app. Please excuse my brevity.


 The way it was explained to me is anything over a category 2, it's the difference between an open casket or a closed casket because the shockwave will turn your insides to jelly.

The everyday 12cal getup is designed so that you only get 2nd degree burns.


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## ecelectric (Mar 27, 2009)

Its a different world


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## Zog (Apr 15, 2009)

mattsilkwood said:


> The way it was explained to me is anything over a category 2, it's the difference between an open casket or a closed casket because the shockwave will turn your insides to jelly.


Some studies suggest that the pressure wave at levels above 40 cal/cm2 can be fatal. Not sure where you get the HRC 2



mattsilkwood said:


> The everyday 12cal getup is designed so that you only get 2nd degree burns.


Um, no. 2nd degree burns can be fatal even with small areas affected. The ATPV rating of PPE means that is the incident energy that it should not allow more than 1.2 cal/cm2 to pass through, which is the on set of a 2nd degree burn. So if your 12 cal/cm2 PPE is exposed to a 12 cal/cm2 arc flash you should only get a 1st degree burn.


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## ecelectric (Mar 27, 2009)

He was wearing a 55 cal suit


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## nitro71 (Sep 17, 2009)

My next question is how common is racking in switchgear while energized? 

I'm thinking this really is for very large sites where it isn't feasible to secure power to the gear.


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## tgreen (Sep 14, 2010)

Racking in breakes on energize dead front switch boards is very common. 
the process for racking in these large breakers would be like this. 

open all the down stream breakers/mains from the breaker that i am intending to close. veryify that all cables have been meggered/ and that they are all landed properly. most of these large frame breakers have multiple sets of parrallel conductors and it can be easy to cross the phases, remove all non essential people from the switch room. reach over to the close button. place my finger on the button and turn my head away from the breaker. let those in the room know that i am about the close the breaker. then push the button. verify that the contact closed window indicats that the breaker is closed. check the load side metering to verify that there is power on all three phases. verify rotation. then i would go down stream and close sub feeds one by one. slowly brining on the full building load.


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## nitro71 (Sep 17, 2009)

TGreen, I think we are talking about two different procedures here. You're talking about closing a breaker. 

Where as Zog, pretty sure, if I have this right is talking about installing or removing a breaker. 

Just so we are all clear on what we are talking about.


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## Rockyd (Apr 22, 2007)

nitro71 said:


> TGreen, I think we are talking about two different procedures here. You're talking about closing a breaker.
> 
> Where as Zog, pretty sure, if I have this right is talking about installing or removing a breaker.
> 
> Just so we are all clear on what we are talking about.


I agree withTGreen's premise - to fully remove all possible load from breaker to be racked out. a quick verifiction prior to racking back in isn't a bad idea either.

That way, only control voltage should be present on the breaker being addressed - no load.


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## Big John (May 23, 2010)

nitro71 said:


> TGreen, I think we are talking about two different procedures here. You're talking about closing a breaker.
> 
> Where as Zog, pretty sure, if I have this right is talking about installing or removing a breaker.


 Ayuh, operating a breaker is different than racking a breaker. Racking is the process of inserting or removing the breaker assembly from the switchgear cubicle.


> My next question is how common is racking in switchgear while energized?


 Very common. It's only within the past year that utility I work for has changed our policy to dead-bus racking. Before that, everything used to be racked energized by hand, and in many outfits it still is. 

We just recently had a flash at a remote plant where the guys went against policy and racked energized. Thankfully nobody was hurt, but the cubicle looks like a charcoal briquette.

-John


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## Rockyd (Apr 22, 2007)

Big John said:


> Ayuh, operating a breaker is different than racking a breaker. Racking is the process of inserting or removing the breaker assembly from the switchgear cubicle. Very common. It's only within the past year that utility I work for has changed our policy to dead-bus racking. Before that, everything used to be racked energized by hand, and in many outfits it still is.
> 
> We just recently had a flash at a remote plant where the guys went against policy and racked energized. Thankfully nobody was hurt, but the cubicle looks like a charcoal briquette.
> 
> -John


????

Always have to wonder when a company is good enough to be on the front edge of safety, why some moron has to buck the system? Especially when you know there are potentially serious risk in making the move...like that they were rookie's or didn't believe that it could happen to them (bullet proof - kind of like "kaboler")?


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## brian john (Mar 11, 2007)

Rockyd said:


> I agree withTGreen's premise - to fully remove all possible load from breaker to be racked out. a quick verifiction prior to racking back in isn't a bad idea either.
> 
> That way, only control voltage should be present on the breaker being addressed - no load.


 
Be design when you start to rack the CB it should open the CB if the operator inadvertly left it closed.

Dead bus racking is WAY SAFER.

As for the comment on multiple cables. The poster never worked for Uncle Sam. I have seen 30 and 60 amp CB's and 100 amp are common. Did a job Sunday all draw out CBs 100-800 most in the 100-225 amp range, one 1600 amp main


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## backstay (Feb 3, 2011)

Here is an typical, older vertical racking breaker. Those stabs on top would be your line and load connections. You wheel this into the cubical, then either hand crank or with an electric motor, raise the breaker. That makes the connection between the buss and the stabs. This is all done(without remote racking) with the door open on a live buss in most places. In a large complex, shutting down the buss can not be done. I worked for 15 years in a large paper mill and did this a least once a week. We didn't even have face shields for years. When I left we had the heavy suit with a hood(I don't remember it's rating) but still no remotes. We also closed them with a switch right on the cubical front but the door was closed. I had one blow when closing, but none while racking.


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## nitro71 (Sep 17, 2009)

backstay said:


> I worked for 15 years in a large paper mill and did this a least once a week.


 
Why would you have to do that once a week?


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## backstay (Feb 3, 2011)

Anytime work had to be done downstream from a breaker(switchgear, transformer, generator or MCC buss) the breakers were opened and racked out. This was a big place, it had about five 6800 volt busses, one 13,800 buss. Each buss would have 1 to 2 tie breakers to connect busses together. Then there were steam turbines and hydro generators that had breakers to connect to the differant busses. I will take a guess(never counted) at least 100 large breakers maybe more, I'm sure more.


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## nitro71 (Sep 17, 2009)

That's interesting. So it wasn't safe to just open the breaker and lock it out for the downstream work?


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## backstay (Feb 3, 2011)

Sometimes the breaker was pulled for R&R or to work on the line. Or a turbine would be shut down for service and it's tie breaker would be pulled so it could be tested and serviced. As I remember, some of these old breakers had no lockout provisions. So lockout would be racking out and locking the rail it ran on or the racking mechanism itself.

This is a typical sub. It has two 6800 volt breakers that feed the transformers(in a differant building)fourteen 575 volt breakers, two main breakers(ties the transformer to the 575 volt buss) and one tie breaker(double ended sub, can be fed from either transformer). You now multiply this room by a least 25 other rooms, you get a lot of medium to large breakers.

I just noticed you can see the lifting rig to get the breakers into their cubicals. It is hanging on the far end, red piece is the hoist.


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## nitro71 (Sep 17, 2009)

Backstay, Thanks for posting that up :thumbsup: That's some serious switch gear you have there.


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## Big John (May 23, 2010)

Rockyd said:


> Always have to wonder when a company is good enough to be on the front edge of safety, why some moron has to buck the system...?


 People are strange. You're being told to do it the safe way, and paid by the hour to take the time to do it, but folks will still cut corners.

I'm betting the tech. had been racking breakers for years on live bus, and like you said, he figured he was invincible because he'd _always_ done it that way. He knew he'd have to get the station taken offline to de-energize that bus, so he tried to take a shortcut and it literally blew up in his face. :blink:

-John


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## backstay (Feb 3, 2011)

This is a small lift station with newer switchgear. I wish I had pictures of the turbine room switchgear room. It had very old to very new breakers, the 6800 and 13,800 volt stuff. But I don't work there anymore and never took many pictures.


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## Zog (Apr 15, 2009)

nitro71 said:


> That's interesting. So it wasn't safe to just open the breaker and lock it out for the downstream work?


Draw out breakers are required to be racked out to the disconnect postiion and locked for LOTO, just opening a breaker does nto meet LOTO requirements


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## Zog (Apr 15, 2009)

backstay said:


> This is a small lift station with newer switchgear. I wish I had pictures of the turbine room switchgear room. It had very old to very new breakers, the 6800 and 13,800 volt stuff. But I don't work there anymore and never took many pictures.


I have thousands, no tens of thousands of photos of older MV switchgear and breakers, I would post but would not know where to begin.


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## Zog (Apr 15, 2009)

backstay said:


> Here is an typical, older vertical racking breaker. Those stabs on top would be your line and load connections. You wheel this into the cubical, then either hand crank or with an electric motor, raise the breaker. That makes the connection between the buss and the stabs. This is all done(without remote racking) with the door open on a live buss in most places. In a large complex, shutting down the buss can not be done. I worked for 15 years in a large paper mill and did this a least once a week. We didn't even have face shields for years. When I left we had the heavy suit with a hood(I don't remember it's rating) but still no remotes. We also closed them with a switch right on the cubical front but the door was closed. I had one blow when closing, but none while racking.


Actually that is a modern version, made in the 1980's or later. That is a vacuum retrofit for the old magneblast I think you are talking about. Same idea for racking though.


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## Zog (Apr 15, 2009)

Rockyd said:


> I agree withTGreen's premise - to fully remove all possible load from breaker to be racked out. a quick verifiction prior to racking back in isn't a bad idea either.
> 
> That way, only control voltage should be present on the breaker being addressed - no load.


How is removing load the same as removing voltage? Unless you have the line side of the breaker de-energized you are still closing, or racking, the breaker on an energized bus. And removing the load has no effect on what the fault would be if there were an issue.


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## Zog (Apr 15, 2009)

Take a look at this presentation, the last few slides cover a couple of racking incidents, one is an old one, the last one is recent. 
http://www.cbsnuclear.com/downloads...ng-and-switching-for-arc-flash-mitigation.pdf


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## Widestance_Politics (Jun 2, 2010)

Zog said:


> Draw out breakers are required to be racked out to the disconnect postiion and locked for LOTO, just opening a breaker does nto meet LOTO requirements


Zog can you clarify whose requirements you are referring too? I was under the impression that the requirements could vary between sites according to what the owner/operators decide. At the last site I was working the LOTO rules were extreme, and one question I had was why we should rack a 13.6kv breaker completely to the disconnect position as opposed to just the test position and locking the racking mechanism.
The 230kv transformer ahead of these breakers was already disconnected from the utility so we were just following the operators protocols for LOTO when we could have been just as safe leaving the breaker racked in and in the open position.
I am not trying to justify not following procedures or anything....just wondering who actually defines and decides them......
Also, to fully disconnect one of these breakers we would have to lift test switches at the relay protection panel or we would send a trip to the main switchyard.....so to fully follow the LOTO we were bypassing safety features.....


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## Zog (Apr 15, 2009)

WP, it depends on the specific breaker type, some can't be properly locked out in the test position, some can. But, my point is just opening it and hanging a lock is not acceptable isolation. And if you have upstream isolation the breaker is just your 2nd point anyways. It depends if you are following NESC or OSHA what the specifics are, and the OEM's LOTO instructions.


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## drsparky (Nov 13, 2008)

Zog said:


> Remote racking is available for vertical lift breaker too.


I should have said we were still manualy racking these old breakers, cold buses only, once a year during shut down for cleaning and testing.


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## sparky.jp (May 1, 2009)

Over the span of my career I have paid close attention to electrical accidents involving the racking in/out of circuit breakers (including the video posted earlier in the thread), and want to add the causes for the accidents in two of the cases that I know of (both cases involved a live bus in the switchgear):

Case 1: The 3-pole circuit breaker was opened before it was racked out, but one pole had NOT actually opened - arc flash while racking out.

Case 2: The 3-pole circuit breaker (in open position of course) had some metallic debris (best guess er "expert opinion", it's hard to tell from the charred remains) between two of the poles on the line side - arc flash while being racked in. And it was a refurbished circuit breaker direct from the manufacturer.

So the advice in this thread is sound, and the threat is real. Even with "new" equipment! Check everything, assume NOTHING. I, too, heartily endorse the remote operator devices (those ones made from a converted hand truck are fine examples of Yankee engineering).

In my first job out of college I was visiting a coal-fired power plant where I got to witness the closing of a large circuit breaker in an ancient piece of switchgear (can't remember voltage level, but I think the gear was almost 50 years old). One "volunteer" went over to operate the breaker, while the rest of the group stayed waaayy out of the way (ZERO PPE back in 1990, yikes). I never really knew what the big deal was until much later, but at least I was smart enough to hang back with the rest of the group!


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## micromind (Aug 11, 2007)

I've racked tons of breakers in hot gear. Every time it makes me a bit more nervous. Most of these are at power plants, usually with the generators running. The bad part about this is the available fault current is higher when the gear is being fed from more than one source. Motors will also contribute to fault current. 

The majority of these breakers can be closed remotely, some cannot. 

The switchgear is usually 15KV, operating at 12.5 or 13.8. Sometimes it's 35KV running at 34.5. That's even more scary.

I didn't know that remote racking was available. I'll have to look in to that; most of the breakers are C/H, they all have a 3/4" hex racking bolt. 

The reason why we always rack a MV breaker out when we're working downstream of it is even if the controls are disconnected and the spring isn't charged, the only thing between you and the line bus is a vacuum bottle. They've been known to leak; though it's rare. If the vacuum bottle has leaked, it'll arc over and energize one of the phases. Bad news!

All MV breakers I've worked with will trip if you try to rack it out while it's closed. Both electrically and mechanically. I always verify with the flags though, and push the mechanical trip button. 

Before I rack it back in, I'll run it out on its rails so I can work on the bus jaws. First I clean the vacuum bottles and insulators, then I'll hi-pot the vacuum bottles. Never had one fail yet, but the day is coming.

It sounds like nuke-suits are made that can at least cut back on the effects of an arc blast; I need to look into one of those too. The one the company has is several years old, I doubt it'd do a whole lot against that sort of energy.


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## Zog (Apr 15, 2009)

micromind said:


> I've racked tons of breakers in hot gear. Every time it makes me a bit more nervous. Most of these are at power plants, usually with the generators running. The bad part about this is the available fault current is higher when the gear is being fed from more than one source. Motors will also contribute to fault current.
> 
> The majority of these breakers can be closed remotely, some cannot.
> 
> ...


 Remote racking has been the norm for most power plants for years, how you have never heard of it amazes me. 



micromind said:


> The reason why we always rack a MV breaker out when we're working downstream of it is even if the controls are disconnected and the spring isn't charged, the only thing between you and the line bus is a vacuum bottle. They've been known to leak; though it's rare. If the vacuum bottle has leaked, it'll arc over and energize one of the phases. Bad news!


 Yep, happens all the time. I had orders for 21 replacement bottles today. Bottles are expected to have about a 25 year life span, with VCB's becoming common in the 80's many are near thier end of life and will require replacement soon. 



micromind said:


> All MV breakers I've worked with will trip if you try to rack it out while it's closed. Both electrically and mechanically. I always verify with the flags though, and push the mechanical trip button.


 Should trip, those racking interlocks are known to fail often. Some have been recalled or has safety notices. 



micromind said:


> It sounds like nuke-suits are made that can at least cut back on the effects of an arc blast; I need to look into one of those too. The one the company has is several years old, I doubt it'd do a whole lot against that sort of energy.


No PPE either?  No arc flash study?


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