Closing a CB for the first time

mayanees

Senior Member
In Table 130.7(C)15(A)(a) where they provide the list of appropriate PPE for tasks, it says the following under the task of operating a circuit breaker:
Under the column heading "Equipment Condition", no additional PPE is required only if;
But, under the following conditions, yes, PPE IS REQUIRED if:

Should there be an injury and a door WAS closed, an OSHA inspector is going to demand DETAILED RECORDS of whether the equipment was properly installed and maintained. The reality is, almost NOBODY has records like that.

And BEFORE that, they provide this "Informational Note"
Jraef, Sir, You are one 70E Code cycle off!
70E 2018 now has Table 130.5(C) Estimate of likelihood of Occurrence of an Arc Flash incident ... and that table defines Normal with 6 conditions that adds "used in accordance with instructions... to the 2015 list.

NFPA 70E, Standard for Electrical Safety in the Workplace is a National Consensus Standard document and as such it's in effect when issued. Unlike NFPA 70 NEC which is voted in by jurisdictions. The logic is that if a Safety improvement has been recognized it's in effect right away.
Of course 70E is not the law, but, (and I think you may have said this in a post some time ago), if there's an electrical fatality at your facility and OSHA shows up, if you don't adhere to 70E, the whole focus of the investigation will turn to comparing your practice to the 70E standard, and good luck with that.
And the newest wrinkle to Electrical Safety is the release of IEEE 1584-2018, referenced of course by NFPA 70E, which changes the way arc flash studies are conducted. I welcome it because it's confusing enough that it'll keep me gainfully employed for years to come!
 

brantmacga

Senior Member
I’ve always felt that statistically, as an electrician, it’s more likely to blow up on you than anyone else.


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Davebones

Senior Member
How do you not stand in front of a I-line 480 v , 600 amp breaker if you have to close it ? Do they make a remote operator for a I-Line style breaker ?
 

kwired

Electron manager
How do you not stand in front of a I-line 480 v , 600 amp breaker if you have to close it ? Do they make a remote operator for a I-Line style breaker ?
Don't laugh and it probably isn't done all that much, but standing off to side and use something for a push stick will put you further away from potential blast than using your bare hand directly on the handle.
 

milmat1

Member
We have had instances where a wiring fault or defective component caused an arc flash upon the first power up. We have engaged the 200A disconnect on new MCC's and had breakers explode, once had a VFD that blew the MOV's out of the case due to wiring faults etc.
So yes the first power up is a time for utmost safety prep...
 

Jraef

Moderator
Staff member
I recently read a nicely done brochure put out by Fluke on this subject, link to follow. But regardless of the REQUIREMENT for PPE or not, this is what I see as important:

If operating a larger frame circuit breaker, especially anything with a frame size of 600 A or greater it would be advisable to wear arc-rated clothing and PPE. It is not mandated by Table 130.5(C), but if the circuit breaker did fail the consequences would far outweigh any consideration given to comfort.A few minutes of discomfort in an arc-rated flash suit and hood is much better than undergoing the pain and suffering of a large-scale burn, no matter how unlikely it may be.
Source, and decent breakdown of the charts:
http://support.fluke.com/find-sales/...00_ENG_A_W.PDF
 

sameguy

Senior Member
Was changing a ballast hot 277v years ago, missed the hole to push the #?16/18awg into, drew an arch off the grounded ballast case that left copper melted into my glass prescription lens. It blinded me for about 10 minutes. I never go to the doctors but did the next day, was told I had welders eye. Feels like your eye was held open and sand poured in.
 
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