Old House Electrical

[Willyou]

Non-grounding receptacles can be replaced with grounding-type where they are fed from a GFCI.  These must be marked "GFCI Protected" and "No Equipment Ground".  A typical GFCI receptacle tester won't work on these, because the tester shunts a small current onto the EGC to trip the GFCI.  So the tester won't work, but they are NEC compliant.

I understand that a series of outlets can be protected by a single gfci outlet if the gfci is the first in line from the main breaker. Does what you said above mean that the down stream outlets must be grounded outlets for this to work?
My SIL tells me that some of his outlets are 3 prong and they are marked as ungrounded (not sure how it is exactly worded). Would that suggest that there is a gfci in the #1 position in that circuit?

[Roly]

I understand that a series of outlets can be protected by a single gfci outlet if the gfci is the first in line from the main breaker. Does what you said above mean that the down stream outlets must be grounded outlets for this to work?
My SIL tells me that some of his outlets are 3 prong and they are marked as ungrounded (not sure how it is exactly worded). Would that suggest that there is a gfci in the #1 position in that circuit?

No, they do not need a ground if they are downstream of the gfci. to work on a ground fault.   I would not assume just because they are marked ungrounded that they are gfci protected.
Also remember the gfci does not prevent you from getting shocked, but is supposed to prevent a lethal shock.    I use a solenoid type voltage tester (Wiggens) and place one probe on the hot side of the outlet and the other probe on to a ground such as a water pipe which will trip the gfci.   A regular digital voltmeter will not draw enough current to trip it.  Grounding of the outlet is the best and safest way Roly

[Willyou]

No, they do not need a ground if they are downstream of the gfci. to work on a ground fault.   I would not assume just because they are marked ungrounded that they are gfci protected.
Also remember the gfci does not prevent you from getting shocked, but is supposed to prevent a lethal shock.    I use a solenoid type voltage tester (Wiggens) and place one probe on the hot side of the outlet and the other probe on to a ground such as a water pipe which will trip the gfci.   A regular digital voltmeter will not draw enough current to trip it.   Grounding of the outlet is the best and safest way Roly

Thanks. That is kinda what I thought. I've asked him to look for any gfci's on those circuits with the new 3 prong outlets. Grounded system is best; understood.

If I'm able to convince him to get the system grounded, understanding that the existing wiring is old and would be best replaced, can it be done by running just a ground wire? And, if so, must it parallel the old wiring or can he find the easiest routes to minimize wall repairs? Slab on grade, I think.

[Roly]

Thanks. That is kinda what I thought. I've asked him to look for any gfci's on those circuits with the new 3 prong outlets. Grounded system is best; understood.

If I'm able to convince him to get the system grounded, understanding that the existing wiring is old and would be best replaced, can it be done by running just a ground wire? And, if so, must it parallel the old wiring or can he find the easiest routes to minimize wall repairs? Slab on grade, I think.

2014 permitted adding a separate ground wire when replacing a ungrounded outlet.   Roly
[font="normal Verdana", Geneva, sans-serif]2014 Code Language:[/font]
[font="normal Verdana", Geneva, sans-serif]250.130© Nongrounding Receptacle Replacement or Branch Circuit Extensions. 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:[/font]
[font="normal Verdana", Geneva, sans-serif](1) Any accessible point on the grounding electrode system as described in 250.50[/font]
[font="normal Verdana", Geneva, sans-serif](2) Any accessible point on the grounding electrode conductor[/font]
[font="normal Verdana", Geneva, sans-serif](3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates[/font]
[font="normal Verdana", Geneva, sans-serif](4) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates[/font]
[font="normal Verdana", Geneva, sans-serif](5) For grounded systems, the grounded service conductor within the service equipment enclosure[/font]
[font="normal Verdana", Geneva, sans-serif](6) For ungrounded systems, the grounding terminal bar within the service equipment enclosure.[/font]

[Willyou]

2014 permitted adding a separate ground wire when replacing a ungrounded outlet.   Roly
[font="normal Verdana", Geneva, sans-serif]2014 Code Language:[/font]
[font="normal Verdana", Geneva, sans-serif]250.130© Nongrounding Receptacle Replacement or Branch Circuit Extensions. 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:[/font]
[font="normal Verdana", Geneva, sans-serif](1) Any accessible point on the grounding electrode system as described in 250.50[/font]
[font="normal Verdana", Geneva, sans-serif](2) Any accessible point on the grounding electrode conductor[/font]
[font="normal Verdana", Geneva, sans-serif](3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates[/font]
[font="normal Verdana", Geneva, sans-serif](4) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates[/font]
[font="normal Verdana", Geneva, sans-serif](5) For grounded systems, the grounded service conductor within the service equipment enclosure[/font]
[font="normal Verdana", Geneva, sans-serif](6) For ungrounded systems, the grounding terminal bar within the service equipment enclosure.[/font]

Thanks. I think I understand all of that.