swd circuit breakers

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T.M.Haja Sahib

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All panels have to have their ratings marked on the nameplate. Additional labels are required for series rated systems. Jim was talking about the rule in 110.24 in the 2011 code that requires service equipment, other than in dwelling units, be marked with the available fault current. Not the rating of the panel and its breakers, but the amount of current that the utility could supply into a fault.

Marking on the enclosure of disconnecting means including that of service equipment containing series connected breakers or fuses with maximum fault current level rating such as

CAUTION ? ENGINEERED SERIES COMBINATIONSYSTEM RATED _______ AMPERES. IDENTIFIED
REPLACEMENT COMPONENTS REQUIRED.

is mandatory for any occupancy (110.22).
 

don_resqcapt19

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Marking on the enclosure of disconnecting means including that of service equipment containing series connected breakers or fuses with maximum fault current level rating such as

CAUTION ? ENGINEERED SERIES COMBINATIONSYSTEM RATED _______ AMPERES. IDENTIFIED
REPLACEMENT COMPONENTS REQUIRED.

is mandatory for any occupancy (110.22).
My comment said that and was a direct reply to your question about markings for fully rated systems.
 

the blur

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and the saftey guys will tell you management is required to provide 70e training and ppe to the store clerk earing $9 per hour to turn on lighting every morning.
 

jim dungar

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and the saftey guys will tell you management is required to provide 70e training and ppe to the store clerk earing $9 per hour to turn on lighting every morning.
Per 70E they only need to be trained and qualified on the task(s) they perform.
 

the blur

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So what is the offical saftey answer ?
to flicking a swd breaker in a 208Y panel. (the most common application of a swd rated breaker)

Figure 150-225 amp sub panel, which is most common on a 208Y.

eye protection only, or ear protection too? or a space suit hood?
 

jim dungar

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PE (Retired) - Power Systems
So what is the offical saftey answer ?
to flicking a swd breaker in a 208Y panel. (the most common application of a swd rated breaker)

Figure 150-225 amp sub panel, which is most common on a 208Y.

eye protection only, or ear protection too? or a space suit hood?

It is up to the employer to decide.
If you are following the 'task tables' of NFPA70E, then the minimum requirements would be Hazard Risk Category 0 clothing.
If you have had calculations performed, then you may decide what PPE is required when you are not within the Arc Flash Boundary (AFB). For example, if the result of the calculation shows an AFB of 2", so you get to decide what clothing is required at a normal working distance of 18".

Usually, the ampacity of the panel has very little to do with the calculated AFB.
 

the blur

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Those tables are for "electrical workers".
Can you apply them to a store clerk flicking a circuit breaker every morning and every night?

and you can't tell me a store clerk is considered an electrical worker for 10 seconds every day when turning on lights :happyno:
 

jim dungar

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PE (Retired) - Power Systems
Those tables are for "electrical workers".
Can you apply them to a store clerk flicking a circuit breaker every morning and every night?

and you can't tell me a store clerk is considered an electrical worker for 10 seconds every day when turning on lights :happyno:
The phrase 'electrical worker' is not contained in NFPA70E, neither is the word electrician. NFPA70E applies to all people interacting with electric, just like fall protection applies to everyone 'above' ground/floor level.
NFPA70E is not mandatory, rather it is one of the standards that OSHA typically cites when levying fines, you are certainly free to ignore it you wish.

I know of one company whose written safety policy says that their employees are outside of the AFB and therefore allows street clothes when using SWD breakers depending upon certain calculated incident energy values.
 
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