Class-A GFCI's are not well suited

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FionaZuppa said:
thats not my claim.
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My apologies if I misunderstood :ashamed1:

my argument was that a GFI (GFCI under NEC) can provide more hazard coverage if an EGC was present.
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Of course. N-2 is better than N-3 contingency coverage.


imho, replacing a 1- with a 5-GFCI leaves room for hazard exposures, thus why i said it should really be a 1:1 swap, a 1-r being replaced by a 1-GFCI, but they dont make 1-GFCI, so i suggested a platic barbed ping to block out the EGC hole on the 5-GFCI, in essence making the swap a 1:1 and keeping it a 1-15R(GFCI).
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So your saying that GFCI protection actually introduces a greater hazard than a missing EGC?




i forget where (NEC or NEMA or UL) stated that the 1- swap to a 5- (not sure if it said 5-GFCI) you can bond the EGC to a proper bond location to gain back the benefit of EGC.


i think what you posted in #58 all comes from OSHA
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I refers to OSHA from my understanding.
 
FionaZuppa said:
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and the faceless is what i was talking about earlier, for applications where class-A just dont work well the use of class-C faceless installed at point of service (w/ single recept or just hardwired) would be ok under UL definitions.

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If the NEC requires GFCI protection, it must be Class A protection. There is no choice here.

The UL standards for appliances and other electrical equipment limit the maximum ground leakage current to 1/2 mA or 10% of the 5mA GFCI trip point.
 
don_resqcapt19 said:
If the NEC requires GFCI protection, it must be Class A protection. There is no choice here.

The UL standards for appliances and other electrical equipment limit the maximum ground leakage current to 1/2 mA or 10% of the 5mA GFCI trip point.
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yesssssssss, i already mentioned art100 definition of "GFCI" says "meets class-A specs".

0.5mA x 10 items = GFCI trip, yes?
but probably not an issue in shear #'s.
 
FionaZuppa said:
yesssssssss, i already mentioned art100 definition of "GFCI" says "meets class-A specs".
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Sorry I missed that, but I find your posts difficult to read and understand, so I probably miss a lot of things.

0.5mA x 10 items = GFCI trip, yes?
but probably not an issue in shear #'s.
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Probably will not trip at 10 items as the 1/2 mA is the maximum permitted leakage current, but it could and a GFCI is permitted to trip at 4 mA. I expect that in many cases the leakage is much less.
 
Class A protection came about due to the electrical communities inquiry to the medical community.

Inasmuch as a pristine path holds true ,the incident of such low R paths is dubious at best

Consider the 30ma RCD , and mortality/morbidity rates....



Further, the objective view is the functionality of a toroidal coil has not changed since it's inception. This is where one needs to rise above code rationale , which often differs from the physical world



~RJ~
 
I am unsure where electrocution stats by country can be harvested.

But it would be interesting to consider the American 5ma system against the Euro 30ma

The earthing system differences might come into play....?

~RJ~
 
romex jockey said:
Class A protection came about due to the electrical communities inquiry to the medical community.

Inasmuch as a pristine path holds true ,the incident of such low R paths is dubious at best

Consider the 30ma RCD , and mortality/morbidity rates....



Further, the objective view is the functionality of a toroidal coil has not changed since it's inception. This is where one needs to rise above code rationale , which often differs from the physical world



~RJ~
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How often do you see a GFCI trip while a person is in the fault current path? Class A protection will protect at that lower limit that can still be fatal, but most of the time the device trips because of equipment failure and current never passes through the people it is there to protect. Still is the chance of a person becoming the fault path though and probably the primary reason we require class A protection on most things that require GFP.

A 30 or even 100 mA device would likely trip in a majority of the cases still protecting the user, but can be more devastating to the user if they are part of the fault current path.
 
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