Difference between GFI and GFCI

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jojo

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Philippines
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Electrical Engineer
hi, good day.. pls help, im a little bit confuse. i just want to know if there's a difference between GFCI and GFI? i have a friend who says that GFCI is for the OCPD in the electrical panels, while GFI is for the individual outlets that has a ground fault current protection. please advise..
 

TOOL_5150

Senior Member
Location
bay area, ca
hi, good day.. pls help, im a little bit confuse. i just want to know if there's a difference between GFCI and GFI? i have a friend who says that GFCI is for the OCPD in the electrical panels, while GFI is for the individual outlets that has a ground fault current protection. please advise..

A GFCI is either a breaker in a panel, or a receptacle. A GFI is a piece of equipment, usually in switchgear that detects a ground fault, and is usually in big services -Greater than 400A. It needs to be set correctly to the service size. Thats about all I know about it, being a resi guy.

~Matt
 

infinity

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New Jersey
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Journeyman Electrician
There is no difference between the terns GFCI and GFI. The latter is just a lazy slang version of the GFCI. The NEC does not even contain the term GFI.

Regarding large wye services as Matt mentioned, they use the term GFPE which has a little different meaning than GFCI.

230.95 Ground-Fault Protection of Equipment.
Ground-fault protection of equipment shall be provided for solidly grounded wye electric services of more than 150 volts to ground but not exceeding 600 volts phase-to-phase for each service disconnect rated 1000 amperes or more. The grounded conductor for the solidly grounded wye system shall be connected directly to ground through a grounding electrode system, as specified in 250.50, without inserting any resistor or impedance device.
The rating of the service disconnect shall be considered to be the rating of the largest fuse that can be installed or the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted.
Exception: The ground-fault protection provisions of this section shall not apply to a service disconnect for a continuous industrial process where a nonorderly shutdown will introduce additional or increased hazards.
 

jojo

Member
Location
Philippines
Occupation
Electrical Engineer
thanks for your advises matt and rob. i was also correct in thinking that either the device is a receptacle or a circuit breaker protecting the feeders, still it is a GFCI. i mean GFI and GFCI is no different. i really appreciate your help..
 
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jumper

Senior Member
thanks for your advises matt and rob. i was also correct in thinking that either the device is a receptacle or a circuit breaker protecting the feeders, still it is a GFCI. i mean GFI and GFCI is no different. i really appreciate your help..

You are correct that GFI and GFCI are the same; however, unlike GFPE-which protects equipment, GFCI protects people.
 

hurk27

Senior Member
You are correct that GFI and GFCI are the same; however, unlike GFPE-which protects equipment, GFCI protects people.

There is also two clases of GFCI's Class "A" is a 5ma device that as said, is a people protector, Class "B" such as the one required in 426.28 is a 30ma device for the protction against fires caused by heating equipment, UL has allowed the use of AFCI's since they include a Class "B" GFCI in them, since AFCI's have come out, Class "B" GFCI's are getting hard to find.
 

jojo

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Location
Philippines
Occupation
Electrical Engineer
yeah derek, GFCI is for safety of persons and GFPE is for equipment. i have to admit that im not really familiar the term GFPE. what i know only know is the terms GFCI and AFCI =) Only when i read yesterday about NEC230.95. Its about a circuit breaker with shunt trip. I came to know that there are 2 types of ground-fault equipment protectors: a ground-fault sensor encircling all circuit conductors (including the neutral) and a ground-fault sensor encircling only the bonding jumper conductor. But what if the service disconnect is rated less than 1000A? is GFPE not required?

@ wayne:thanks for the information regarding the two classes of GFCI. the receptacles in the kitchens and in the wet areas class "A" GFCI's. for class "B" GFCI's i have no idea on its applications for heating equipment. is the class "B" applied for equipments like a microwave ovens?

thanks for the information guys.
 

jumper

Senior Member
Hey jojo,

GFPE is out of my range of experience. I leave that up to an EE.

The 30 mA GFCI protection in a AFCI I knew about, but a class "B" GFCI is a new one to me. There is a lot I do not know.
 

hurk27

Senior Member
Class "B" GFCI's are required in these articles:

424.99(C)(5)
426.28
427.22

And a much missed Class "A" GFCI requirement
424.44(G) although manufactures have been very good about warning labels on this requirement, and even have built in GFCI's in there supplied controls to meet this requirement, but this wasn't so back a few years.

I might have missed others?

I like the idea of using a class "B" GFCI on most cable and element types of heating, as a ground fault somewhere mid cable/element will not always open the OCPD, and this can lead to a fire or shock hazard. so to me it should be required on all resistive type of heating where a ground fault could cause the above to happen.
 

hurk27

Senior Member
@ wayne:thanks for the information regarding the two classes of GFCI. the receptacles in the kitchens and in the wet areas class "A" GFCI's. for class "B" GFCI's i have no idea on its applications for heating equipment. is the class "B" applied for equipments like a microwave ovens?

thanks for the information guys.

Nope mainly resistive type of heating, not all but some as in the articles I listed above.;)
 

jojo

Member
Location
Philippines
Occupation
Electrical Engineer
@ derek: thanks. i should ask EE for more info about GFPE.
@ wayne: i've got a copy of NEC here. =) i'll read the articles you cited. thanks.
 
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don_resqcapt19

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Location
Illinois
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retired electrician
Does anyone make Class B GFCI breakers anymore? There were for swimming pool lights in codes prior to 1965 and have a 20 mA trip point. The ground fault protection breakers that I have used for heat trace all have a 30 mA trip and are not called GFCIs.
 

hurk27

Senior Member
Does anyone make Class B GFCI breakers anymore? There were for swimming pool lights in codes prior to 1965 and have a 20 mA trip point. The ground fault protection breakers that I have used for heat trace all have a 30 mA trip and are not called GFCIs.

Apparently Square-D still does :

QO-EPD circuit breakers with 30 mA equipment ground-fault protection (1-pole, 2-pole, 15 A to 60 A; 3-pole, 15 A - 50 A)
Earthing Protection Device?

There not called class "B" but a new class "1" ?:confused:

also it is very common for Europeans to use a 30ma type called "Earth Leakage Breakers"
 

don_resqcapt19

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Location
Illinois
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retired electrician
Wayne,
Yes SquareD makes a 30 mA trip device but a Class B GFCI has a 20 mA trip. I have used the SquareD EPD breakers many times for heat trace, but I have not seen any information that calls them a Class B GFCI.
My question was only to the availability of a device that is marked as a Class B GFCI.
 

hurk27

Senior Member
Wayne,
Yes SquareD makes a 30 mA trip device but a Class B GFCI has a 20 mA trip. I have used the SquareD EPD breakers many times for heat trace, but I have not seen any information that calls them a Class B GFCI.
My question was only to the availability of a device that is marked as a Class B GFCI.

I have done various searches in about all the search engines I have on here, and the only mentioning of a class "B" GFCI is in the many code forums out there, I haven't been able to pull up one listing of a class "B" GFCI but I can find many one a class "1" GFCI such as the 30ma one I posted above from Square D. so maybe the term class "B" is a hold over from the 20ma days? and is no longer correct.
 
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