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  • Hv&Lv
    replied
    I believe it says. ”normal operation of a well-functioning circuit breaker/contactor does not require any PPE (unless there open doors/covers).“

    fuel for this fire... is a brand new, “never been energized on this job” breaker “well functioning”?


    https://www.depts.ttu.edu/opmanual/OP60.14B.pdf

    http://support.fluke.com/find-sales/...00_ENG_A_W.PDF

    Leave a comment:


  • sameguy
    replied
    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.

    Leave a comment:


  • Jraef
    replied
    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

    Leave a comment:


  • milmat1
    replied
    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...

    Leave a comment:


  • kwired
    replied
    Originally posted by Davebones View Post
    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.

    Leave a comment:


  • zog
    replied
    Originally posted by Davebones View Post
    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 ?
    Yes, page 108

    https://www.cbsarcsafe.com/wp-conten...2015_lores.pdf

    Leave a comment:


  • romex jockey
    replied
    They make a 'handle' that allows some leverage , but it's usually not very long ~RJ~

    Leave a comment:


  • Davebones
    replied
    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 ?

    Leave a comment:


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


    Sent from my iPhone using Tapatalk

    Leave a comment:


  • mayanees
    replied
    Originally posted by Jraef View Post
    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!

    Leave a comment:


  • jaggedben
    replied
    One guy I worked with told a friend of his died after he left a wrench against the busbars in a residential panel and turned on the breaker. This was in the context of replacing a 200A main breaker on a resi panel and the guy stood to the side and used a broom stick to turn on the replacement. Just in case.

    It's not the breaker that will blow up, most times.

    Leave a comment:


  • Jraef
    replied
    Originally posted by Strathead View Post
    If all covers are in place, there should be no requirement for PPE and no more risk than that of getting struck by lightning on a sunny day. The only caveat would be a true bolted fault on a breaker who's AIC rating was calculated so incorrectly that the hedge factors in everything are overcome.
    Originally posted by Strathead View Post
    Can you quote a source that requires PPE when all covers are in place?
    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;
    All of the following:

    The equipment is properly installed
    The equipment is properly maintained
    All equipment doors are closed and secured
    All equipment covers are in place and secured
    There is no evidence of impending failure
    But, under the following conditions, yes, PPE IS REQUIRED if:
    One or more of the following:

    The equipment is not properly installed
    The equipment is not properly maintained
    Equipment doors are open or not secured
    Equipment covers are off or not secured
    There is evidence of impending failure

    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"
    Informational Note No. 2: The collective experience of
    the NFPA 70E Technical Committee is that, in most cases,
    closed doors do not provide enough protection to eliminate
    the need for PPE in situations in which the state of the
    equipment is known to readily change (e.g., doors open or
    closed, rack in or rack out).

    Leave a comment:


  • kwired
    replied
    Originally posted by Fulthrotl View Post
    yeah. me.

    i closed a main breaker on a residential panel, with all the
    covers properly in place. the arc came crawling out between
    the cutout hole, and the edge of the breakers, burnt the skin
    off the back of the middle two fingers on my right hand..

    you need to wear PPE. you can quote me if you need to.
    Yet we are required by code make these things readily accessible, which is also readily accessible to the unqualified, makes a lot of sense right?

    But OSHA is only for the employed, so what if others are in any danger I guess. Now comes the manager at an office building or other employee in similar situation that doesn't ordinarily do any electrical work tasks that tries to reset a tripped breaker in their office building - I guess we should at least be putting big warning signs on this equipment that only qualified individuals can even open the dead front cover and operate any devices inside, though I anticipate even that will get ignored most the time.

    Typical dwelling, the available incident energy isn't that high all that often to be able to do that, but sometimes it is.

    Leave a comment:


  • Fulthrotl
    replied
    Originally posted by Strathead View Post
    Can you quote a source that requires PPE when all covers are in place?
    yeah. me.

    i closed a main breaker on a residential panel, with all the
    covers properly in place. the arc came crawling out between
    the cutout hole, and the edge of the breakers, burnt the skin
    off the back of the middle two fingers on my right hand..

    you need to wear PPE. you can quote me if you need to.

    Leave a comment:


  • romex jockey
    replied
    Seems the tenured sparks aways have their anecdotals.

    Myself i was blind for what was the worst 5 minutes of my life......so far...

    None of this is necessarily our own neglect , miswiring, whatever....

    You guys all know the 'ol bold electrician addage .....

    ~RJ~

    Leave a comment:

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