GFIs

[zog]

"I always saw these as two abreviations for the same thing. GFI seems to be an older phrase while GFCI is being used more recently"

They are very different devices with very different purposes.

 

[petersonra]

210.8(B)(4) says this about ?outdoors in public spaces?:

The NEC does not say what it means by ?the public.? Article 525 uses the phrase ?general public,? and that phrase is not defined either.

My interpretation is that ?the public? is everyone who does not qualify as being a ?Qualified Person.? That term is defined in Article 100, and includes people who have skills, knowledge, and safety training in the construction and operation of electrical equipment. A High School student who is working the cotton candy machine as a summer job is not a ?Qualified Person.? I think that student should be counted as a member of the ?public,? or if you prefer, the ?general public,? and that the student should not be excluded from either group simply because he or she is being paid to be there.

If the phrase "general public" actually means "not a qualifed person" as in your interpretation, why would the code makers not have used that phrase, since it is well defined?

I can't imagine any reasonable interpretation of the English language that would allow for your interpretation.

 

[charlie b]

I can't imagine any reasonable interpretation of the English language that would allow for your interpretation.

As you wish. But why is it OK to limit protection to the person standing outside the booth buying cotton candy, and not to protect the person standing inside the booth operating the cotton candy machine? Why is one a member of the public, and not the other? We are professionals in this industry; they are not.

 

[roger]

They are very different devices with very different purposes.

Zog, actually as far as trade lingo, GFI and GFCI are the same, however, GFP is a different animal for equipment protection.

Ground-Fault Circuit Interrupter (GFCI). A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device.

FPN: Class A ground-fault circuit interrupters trip when the current to ground has a value in the range of 4 mA to 6 mA. For further information, see UL 943, Standard for Ground-Fault Circuit Interrupters.

Ground-Fault Protection of Equipment. A system intended to provide protection of equipment from damaging line-to-ground fault currents by operating to cause a disconnecting means to open all ungrounded conductors of the faulted circuit. This protection is provided at current levels less than those required to protect conductors from damage through the operation of a supply circuit overcurrent device.

Roger

 

[zog]

Well the "trade lingo" is wrong. A GFI is one type of GFP.

I was training a group of OSHA inspectors recently and this topic came up, one guy was investagating a fatal accident from a facillity that did not use GFCI's for portable tools because they were led to believe the GFI on thier main feeder would protect workers from shocks.

 

[petersonra]

As you wish. But why is it OK to limit protection to the person standing outside the booth buying cotton candy, and not to protect the person standing inside the booth operating the cotton candy machine? Why is one a member of the public, and not the other? We are professionals in this industry; they are not.

I am not saying it is not a good idea to put GFCIs inside the trailer, only that it is an extreme stretch to suggest the term "general public" includes people who have the key to the trailer. The general public has no access to the inside of the trailer, or at least no authorized access.

If you think this is enough of a good idea to mandate it, why not put forth a proposal to require it?

I think you might have a better argument calling the trailer a kitchen and suggesting it needs GFCIs because it is a kitchen, as it clearly meets the definition of a kitchen, as regards GFCI requirements.

210.8 (B) Other Than Dwelling Units. All 125-volt, singlephase,
15- and 20-ampere receptacles installed in the locations
specified in (1) through (5) shall have ground-fault
circuit-interrupter protection for personnel:
(2) Commercial and institutional kitchens—for the purposes
of this section, a kitchen is an area with a sink and permanent
facilities for food preparation and cooking

 

[Mr. Bill]

I found this doing a web search. It says GFI can mean either. Probably why newer verions of the NEC is more specific about GFCI and GFP.

ground fault
GFI (Ground Fault Interrupter)
GFI is generic term referring to both GFCI and GFP
GFCI (Ground Fault Circuit Interrupter) see GFI
A device intended for the protection of personnel that functions to de-energize a circuit, or portion thereof, within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.
GFP (Ground Fault Protector) see GFI
A device intended to protect equipment by interrupting the electric current to the load when a fault current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protection device of that supply circuit.

 

[charlie b]

If you think this is enough of a good idea to mandate it, why not put forth a proposal to require it?

Because I don't feel that strongly about it. :roll: :wink:

But if I try to come up with a reason that this requirement (i.e., GFCI for outdoor receptacles that are accessible to the public) is in the code, I think of someone looking for a place to plug in some old piece of junk that is in questionable condition. Then I think of the cotton candy machine inside the concession stand. I am guessing these sorts of things are probably old pieces of junk themselves.

So as a matter of good design practice, I would want to have the receptacles inside the concession stand protected by GFCI. And if I were the Inspector (don't worry, there is no danger of that happening ), I would think about requiring GFCI, using my interpretation of "the public" as the basis for my call.

 

[charlie b]

Probably why newer verions of the NEC is more specific about GFCI and GFP.

What the NEC is specific about is "protection for personnel" versus "protection for equipment."

 

[roger]

Well the "trade lingo" is wrong.

Sorry, but that is only your opinion, take it from someone that deals with installers on a daily basis, GFI and GFCI are referring to the same thing in the real field.

A GFI is one type of GFP.

Agreed, but you'd be better off referring to them as Class A and Class B GF devices

I was training a group of OSHA inspectors recently and this topic came up, one guy was investagating a fatal accident from a facillity that did not use GFCI's for portable tools because they were led to believe the GFI on thier main feeder would protect workers from shocks.

Perfect example of why GFI and GFP with explanations of the difference in Class A and Class B should be used in these training sessions.

Roger

 

[jim dungar]

Sorry, but that is only your opinion, take it from someone that deals with installers on a daily basis, GFI and GFCI are referring to the same thing in the real field.

Agreed, but you'd be better off referring to them as Class A and Class B GF devices



Perfect example of why GFI and GFP with explanations of the difference in Class A and Class B should be used in these training sessions.

Roger

GFCI - Ground Fault Circuit Interrupter - specifically defined by UL (Class A) in UL 943- 6mA trip point. GFCI was also used with the older UL Class B 20mA device that was intended for pooL lighting (back in the 60's).

GFI/GFP/GFPE - are all other ground fault protective devices under UL 1053.

In my area we call GFI the service entrance type stuff (i.e. NEC 230), and GFP/GFPE the 30mA devices for small equipment and resistance heating.

I don't know if UL changed their standards, but it seems that now some manufacturers are calling 30mA devices as Class B protection, although I have not seen them called GFCIs.

 

[roger]

Jim, UL still refers to Class B as being at 20ma I believe and they are under GFCI.

Roger

 

[jim dungar]

Jim, UL still refers to Class B as being at 20ma I believe and they are under GFCI.

So what does UL call a 30mA ground fault protective device?

I thought, in a previous post you inferred a 30mA was a Class B device, was I mistaken?

 

[roger]

So what does UL call a 30mA ground fault protective device?

I would think that anything above a Class A would be a Class B until someone wants to add some classifications.

FPN: Class A ground-fault circuit interrupters trip when the current to ground has a value in the range of 4 mA to 6 mA. For further information, see UL 943, Standard for Ground-Fault Circuit Interrupters.

I thought, in a previous post you inferred a 30mA was a Class B device, was I mistaken?

I think you are mistaken, at least as far as this thread is concerned.

Roger

 

[jim dungar]

I would think that anything above a Class A would be a Class B until someone wants to add some classifications.

That would follow with what some manufacturers say.

But, according to the UL White Book guides:
FTTE - ground fault devices 6-50mA are not GFCIs.
KCXS - GFCIs, Class B (20mA) devices are intended for swiming pool fixtures installed prior to 1965.
KCYC - special purpose GFCIs, Class C, D, and E
KDXA - ground fault protection for services and feeders

I wonder what UL will call the combination AFCI/GFCI that supposedly trips at 30mA?

 

[don_resqcapt19]

Jim,

I wonder what UL will call the combination AFCI/GFCI that supposedly trips at 30mA?

I don't think that they call the standard AFCI an AFCI/GFCI even though all AFCIs have a ground fault protection circuit. CH has an AFCI that also has a listed Class A GFCI built into it. I don't know what they call it as "combination" is not the correct term. The AFCI currently in use is a "branch circuit/feeder AFCI". Starting the next year we will be required to use what is called a "combination" AFCI. That device is said to provide protection beyond the wiring system outlet. The one currently in use provides only very limited protecion beyond the outlet.
Don

 

[kboomb]

Thank you for all of the replies
The answer I am looking for on the Trailers is GFI protection feeding it.
At the street we have under ground electric into j boxes with pin and sleeve
plugs. We plug the panels into this system and this works very well.The sq d panels have 50 amp gfi 2 pole breakers feeding the concession trailers and When it rains I can not keep them on. We just bought
Manufactured temporary panels and they do not gfi protection the 50 amp
2 pole receptacles these are a 4 wire. We have use the new panels for
one season and this has worked very well. I am afraid If these boxes have gfi
in them they will be taken out by other electricians. Also we do not want
some one hurt. I need an answer because more of the units are going to be bought
Bobby