Non Grounding Receptacles

[copper123]

I just looked at a job yesterday. The owner has old, cloth covered romex without a ground. They asked me about ways to combat the problem. I explained about using a GFCI as in 406D3. The owners told me that two other contractors had told them about running a external ground wire to the ground on the recep. I asked them where they thought the contractors were going to bond to. The reply was to a ground rod and the well case. After thinking about this, I have seen this application done before, but goodness, It surely can't be in the code (I have looked) and it goes against all sound current flow/trip principles that I have learned. Am I missing something? Even at 25 ohms on a rod, you have what, 4.8 amps of current flow? Anyhow, has anybody seen this and can someone set me strait if this practice is at some level safe.
Thanks

 

[copper123]

Re: Non Grounding Receptacles

Also:
Can anybody tell, or have a crash course lesson on how to tell if the old cloth covered romex is asbestos infected or not?

 

[johndeereman]

Re: Non Grounding Receptacles

The training that I have had in the past on asbestos is that the only true way to find out if any thing is asbestos is to have it tested by a lab. As far as running a seperate ground to some outlets form a ground rod to make them grounded is not a proper way to do this as per the NEC the equipment ground is to run with the supply conductors & if you think about this @ the first point of service the grounds & neutrals are tied togeter & your not relying on just a single ground rod to ground the receptacles which is also a code violation.

 

[jimwalker]

Re: Non Grounding Receptacles

The purpose of the ground prong on a receptacle is clear a fault.Ground rods are for lightning and ground potential differance between ground and the neutral.If they need or want grounded outlets then proper way is by running new wire.Chances are high that that wire is already brittle and that is more of a danger than lack of a ground.Other than for a few items the need for a ground is no longer a problem.Offer them some choices like ground fault breakers or receptacles.rewire,or perhaps just new circuits to the items they need it for.Frigs,computer,microwaves,washing machine.Be carefull in bidding.Often you will find the old boxes too small to put a gfci in them.

As to the aspestus issue i would leave old wires in the wall.The harm is from trying to remove without causing them to flake off.

[ September 03, 2005, 07:02 PM: Message edited by: jimwalker ]

 

[LarryFine]

Re: Non Grounding Receptacles

Copper, the grounding conductor must have a direct, low-impedance pathway back to the service neutral.

I would suggest running a new circuit for loads specifically requiring a ground, such as appliances, computers, outdoors, etc., and leaving the existing lighting receptacles as they are.

GFCI protection, as you mentioned, is the best (non-intrusive) way to improve safety on these circuits.

 

[dana1028]

Re: Non Grounding Receptacles

Take a look at 250.130(C)(1)& (2). The equipment grounding conductor of a grounding-type receptacle or a branch circuit extension shall be permitted to be connected to any of the following:

(1) ANY accessible point on the grounding electrode system as described in 250.50
(2) ANY accessible point on the grounding electrode conductor

A ground rod is a component of the grounding electrode system.

Remember...you are not taking your fault to ground in this scenario....you are taking it to the ground rod which is connected to the grounding electrode conductor which is connected to the neutral bus in the panel......a fault takes ALL availables paths and follows the path(s) of least resistance back to the source. Yes a very little current will flow onto the ground rod but due to the high resistance the majority of the current will flow on the electrode conductor back to the neutral bus and thus the source.

Read 250.130, then move over to (C)

 

[George Stolz]

Re: Non Grounding Receptacles

Originally posted by copper123:
It surely can't be in the code (I have looked) and it goes against all sound current flow/trip principles that I have learned.

I think what everybody's saying is, you're dead on correct.

Ask who the other contractors were, and either turn 'em or teach 'em.