No grounds - Revisited

[bjp_ne_elec]

One thing that wasn't clear to me from a previous post about this topic was what you officially had to do, it you added to an existing circuit that did not contain the new properly sized ground. If you read my last post, the NM cable that I found in this particular house has a reduced size ground - and in most cases, I couldn't get a full 120 V from the hot to the ground.

In about 1/2 the junctions I checked, I found it totally open - on others I got a dim light on my Ideal "Idiot" Light.

What I would like to do, is extend the circuit to add two set of Dual-Headed floods - one in the front of the garage and anther off the back deck. But obviously, these would involve metal WP boxes - now what's the deal with grounding.

I'm clear (at least I think I am) I could only change out ungrounded with receptacles with GFCI - with the caveat that I have to label them "No Equipment Ground" - and I do have to do this on a defective non-grounded receptacle in the garage.

Just not sure if I can extend this circuit for adding the Floods.

Thanks,

Brettt

 

[LarryFine]

I again recommend taking a day and connecting all of the unconnected undersized EGC's throughout the house (don't forget checking inside the panel.)

Whether you consider them adequate for the job or not (I do, in existing work), they're better than nothing, and you can still use GFCI's anywhere you like.

Granted, the undersized EGC may not suffice for long-term circuit capacity, but that's not its job. In a short-circuit, it should be able to trip a breaker or fuse.

In any case, for outdoor lighting in metallic bodies and enclosures, especially in wet conditions, I'd feel a lot safer while on a ladder changing bulbs, GFCI or not.

 

[bjp_ne_elec]

Larry - considering the 2005 NEC, am I allowed to extend the existing circuit, considering the EGC in the HR is undersized. That's what I'm struggling with.

Thanks,

Brett

 

[LarryFine]

Larry - considering the 2005 NEC, am I allowed to extend the existing circuit, considering the EGC in the HR is undersized. That's what I'm struggling with.

Brett, if this were an easy one, we wouldn't be debating it, or end up with a 100-page thread. Both sides of the argument have merit. This is basically an extension (pardon the pun) of the circuit-extension-requires-GFCI debate.

Keeping in mind that I believe a receptacle added to an existing circuit need only continue the characteristics of that circuit, I would accept an extension as long as the EGC is properly made up all the way back to the source.

 

[don_resqcapt19]

the NM cable that I found in this particular house has a reduced size ground - and in most cases, I couldn't get a full 120 V from the hot to the ground.

The reduced size of the EGC is not the reason why you can't measure 120 volts. There is an open in the ground path. Even the reduced size ground will read 120 volts when it is connected back to the main bonding jumper.
Don

 

[bjp_ne_elec]

Don - you are correct. I addressed this in the previous thread. I had mentioned I get some circuits where the ground is open, and others that have an open ground - and actually some that have some high resistance (because the Ideal "idiot" light will light, but varies with dimness).

Thanks,

Brett

 

[don_resqcapt19]

Brett,

and actually some that have some high resistance (because the Ideal "idiot" light will light, but varies with dimness).

If by "idiot" light you mean the neon lights in a plug in tester, you would have to have millions of ohms of resistance so that the resistance would drop enough voltage to dim a neon lamp. For all practical purposes that would be an open.
Don