New procedure reduces dangers at power plant

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Jraef

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Nice. Great demo of the technology in action.

But it seemed odd to me that they showed the remote racker being connected with the door open and the guys did not appear to have the proper PPE. Hard to believe that this gear would classify as HRC-0 with the door open, as evidenced by no face shields and no gloves (although technically I think gloves are required even at HRC-0).

Oopsie... :ashamed1:
 

zog

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Charlotte, NC
But it seemed odd to me that they showed the remote racker being connected with the door open and the guys did not appear to have the proper PPE. Hard to believe that this gear would classify as HRC-0 with the door open, as evidenced by no face shields and no gloves (although technically I think gloves are required even at HRC-0).

Oopsie... :ashamed1:
That is a grey area in 70E, the whole "Interaction that is likely to cause an arc flash event" line they use. The 70E refers to task in the tables as examples like racking or operating a breaker, taking voltage measurements, or opening a cover to expose bare energized parts. For this type of breaker opening that door does not expose any bare energized parts so it is easy to argue that PPE is not required if you are not going to operate or rack that breaker. Some plants still require PPE to do it though, but most don't.
 

hillbilly1

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Nice. Great demo of the technology in action.

But it seemed odd to me that they showed the remote racker being connected with the door open and the guys did not appear to have the proper PPE. Hard to believe that this gear would classify as HRC-0 with the door open, as evidenced by no face shields and no gloves (although technically I think gloves are required even at HRC-0).

Oopsie... :ashamed1:
I was thinking the same thing, especially if that is a supposedly failed switch, just connecting the racking mechanism could move something enough to cause a catastrophic failure.
 

Hv&Lv

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Why would any of PG&E work practices come under NFPA 70E? Same as NEC. 90.2 (B)(5)
 

cornbread

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Appreciate the post. After a long debate over the cost and safety we recently purchased a remoting racking device for our site. The video is great, kind of validates what we did.
 

hillbilly1

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Atlanta,Ga
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Field coordinator/ technical support
Appreciate the post. After a long debate over the cost and safety we recently purchased a remoting racking device for our site. The video is great, kind of validates what we did.
Definitely the way to go, much safer than standing in front of it and cranking it in and out! We do not have any customers that have those type breakers, but it would be worth the while buying one if we did.
 

zog

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Charlotte, NC
I would say in 15-20 years from now as robotics become much lower cost we may see much more use of it in many of the more dangerous jobs we perform, even in taking voltage/current readings?
Most switchgear today is available with on board remote racking and switching. That is the future, the problem is the existing gear that will be around for another 40 years.
 
That is a grey area in 70E, the whole "Interaction that is likely to cause an arc flash event" line they use. The 70E refers to task in the tables as examples like racking or operating a breaker, taking voltage measurements, or opening a cover to expose bare energized parts. For this type of breaker opening that door does not expose any bare energized parts so it is easy to argue that PPE is not required if you are not going to operate or rack that breaker. Some plants still require PPE to do it though, but most don't.
I would agree that an open or closed door would make marginal difference. If there is no action taken besides of positioning the breaker on the rails with the remote operator, but not beginning to move the breaker into the cubicle and onto the stabs, it is OK.

Where I would see a problem is the other part of the action, eg. when a breaker is in position, breaker open but main stabs are still connected and it needs to be removed. The action of connecting the remote racking device to the breaker is where I see the potential problem. Door open or closed, does not matter.
 
Most switchgear today is available with on board remote racking and switching. That is the future, the problem is the existing gear that will be around for another 40 years.
There is absolutely no reason why the motor that is charging the breaker closing and opening springs can not be used to rack the breaker in/out. That, combined with arc-resistant gear construction, is the ultimate solution.
 

SG-1

Senior Member
Here is an on board model. For a picture you have to click on documentation & down load the PDF.

http://www.eaton.com/Electrical/USA...ear/VacClad-WMotorizedRemoteRacking/index.htm

I remember seeing a GE Magnablast line up with this feature. The design was such that you only needed one motor. The operator would slip it into the section that needed to be racked. The motor was small, you could easily carry it around in one hand.
 
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