Two wire receptacle
- Thread starter domnic
- Start date
- Status
That's pretty much it- many get disappointed when they are told that new wire has to be pulled for a fridge b/c of the lack of an egc, but that's the way it is.
There are exceptions for double insulated stuff- but when was the last time you something that was double insulated w/a 3 prong plug?
Ability to install grounded receptacles.
This
V V V V
Also Dominic, remember that in areas required to have gfci protection there is often the presence of plumbing/water/ or other grounded objects, and a break in the cord could expose someone to a significant hazard if they got between the two- the egc in that scenario would provide no protection, but a gfci would.
An egc doesn't replace gfci, and vice versa.
no egc
no egc
My question is by the NEC what good is a three wire receptacle with no egc on a up stream gfci if by the nec you cant use a three wire plug in it I know it provides gfci protection I also people will use it as a with three wire plug .
no egc
My question is by the NEC what good is a three wire receptacle with no egc on a up stream gfci if by the nec you cant use a three wire plug in it I know it provides gfci protection I also people will use it as a with three wire plug .
For general purpose receps you can. If someone is going to plug a fridge or sump pump in their living room, well, not much we can do about that.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Remember, if you are under the 2014 NEC, the act of replacement of the existing two wire receptacle invokes 406.4(D)(4), the requirement for AFCI.
Now that the Leviton AGTR1 Outlet Branch Circuit dual AFCI / Class A GFCI is available, you have another option to solve the problem.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
You know, this is a great question. After sitting a bit with 250.114, and thinking about the common real world wiring situations that will have existing two-wire ungrounded branch circuits, it occurs to me that probably the most likely use will be plugging in the inexpensive outlet strip. These real world situations are residential living spaces mostly full of two wire ungrounded devices.
- Location
- Illinois
- Occupation
- retired electrician
Maybe...if you have something with a 3 wire cord that is not on the list in 250.114(3), you can plug it into the 3 wire receptacle that is GFCI protected and does not have an EGC run to it.
Now for the $64,000 Question: How many homeowners are aware of this Code, how many will actually follow it, and more to the point........... how many care?
JFletcher
Senior Member
- Location
- Williamsburg, VA
What is the problem with using certain appliances on a GFCI w/no EGC? a GFCI doesnt need a ground to function properly, so why the restrictions on what you can plug into one w/o one?
A gfci can fail........
So now you can have a non functioning gfci and a lit up case with no egc. If something was manufactured w/ a 3 prong plug, it has been determined that a hazard would exist should there be a fault to exposed parts.
- Location
- Massachusetts
I think it may be because GFCIs do not always prevent a shock, they just limit how long you get it
Think of a refrigerator with no EGC, it ground faults but it is sitting on plastic wheels on a hardwood floor so there is no current flow, it sits there live maybe for a long time.
Now one day you happen to touch the fridge and the sink at the same time, ZAPP! You will get blasted until the current through your body rises to 6 ma or so and the GFCI opens. This all takes time.
If I remember correctly the member here zog got hung up on 120 messing with a pump in a pond or something until a GFCI tripped. He said it seemed long and painful.
JFletcher
Senior Member
- Location
- Williamsburg, VA
This may have to do with the new 2015 req for self-testing GFCI as well. Same fridge with EGC faults (hot breaks on appliance lamp shellholder and touches painted frame). EGC may have near zero impedance, but that painted frame does, so same fridge is still energized on the shell and amperage draw on the short isnt enough to trip the breaker. Same problem.
Time basically stops when you are getting shocked.
What article lists what appliances cant be used unless an EGC is present? eta nm found it 250.114(3).
- Location
- Massachusetts
- Status