3 light tester?

[Christopher Currins]

Most, not all, 3-prong receptacles, showed correct using two different 3 light testers. Problem they were only wired with 12-2, no ground connection at receptacle. I opened one and it appears there is a ground clipped off at entrance. There are only 2 grounds at 1 of 2 panels, they are marked for AC. Most GFCI's tested open ground as did a few rec.

Pics are of each panel and rec. in question.

[Robert Meier]

It's likely that the cut of EGC in the metal box is making contact with the box so when the recpetacle is screwed to the box the tester shows that it is grounded. Technically it is grounded just not properly or to code. Also the white conductors used as ungrounded conductors in the raceway are a violation. There are a few other visible problems here as well.

[Bob Elliott]

Reason 23 why I think Romex sucks.
At least with conduit you have ground built in.

I did Will county yesterday and the stuff was piled up in a ball in the attic but it would take some fancy bending to mess it up with pipe that way.

How do they get ground in now, Chris?

[Jeffrey R. Pope]

Metal screw through the receptacle to the grounded metal box = a grounded outlet according to the three-light tester.

If you were using a real tester, you would likely have found the "ground" to be inadequate.

A SureTest will give an "open-ground" indication if there is too much impedance on the grounding connection.

[Robert Meier]

Originally Posted by jpope

A SureTest will give an "open-ground" indication if there is too much impedance on the grounding connection.

How sensitive is that tester? I would seem that if the clamp were screwed tightly against the bare EGC and the device mounting screws were tight the test would pass. Am I correct? I've never used the SureTest.

[Jeffrey R. Pope]

Possibly. Anything over 3 ohms resistance on the egc will register as an open-ground. A solid connection will register as a proper ground.

If resistance is too low (less than 0.01 ohms) on the neutral, it will indicate a false ground.

The SureTest is not "fool-proof," but it is a far superior tool than the dummy-lights.

[Robert Meier]

Originally Posted by jpope

Possibly. Anything over 3 ohms resistance on the egc will register as an open-ground. A solid connection will register as a proper ground.

If resistance is too low (less than 0.01 ohms) on the neutral, it will indicate a false ground.

The SureTest is not "fool-proof," but it is a far superior tool than the dummy-lights.

Thanks for the info.

[Jeffrey R. Pope]

Correction - I just looked at the specs and it will register an open-ground as anything above 1.5 ohms resistance on the egc.

[Christopher Currins]

Originally Posted by Robert Meier

It's likely that the cut of EGC in the metal box is making contact with the box so when the recpetacle is screwed to the box the tester shows that it is grounded. Technically it is grounded just not properly or to code. Also the white conductors used as ungrounded conductors in the raceway are a violation. There are a few other visible problems here as well.

What other problems? I'm aware of white not properly identified, and a few double taps. Here is a better pic of panel #2. There are 2 panels each fed separately from meter. Note in other panel, in first post, there are no grounding conductors, yet I tested most all rec. and most tested correct. I wish I would have pulled more. Is it possible all metal boxes are connected with a grounding conductor?

[Robert Meier]

Photo 1 has an EGC and neutral under one screw. Photo 2 the aforementioned white ungrounded conductors in a raceway. Is the panel in photo 2 a subpanel or a service? If it's a service I can't see the main bonding jumper between the neutral and the enclosure. Many unsecured cables.

[Jeffrey R. Pope]

Originally Posted by ccurrins

Is it possible all metal boxes are connected with a grounding conductor?

Very unlikely.

[Christopher Currins]

Originally Posted by Robert Meier

Photo 1 has an EGC and neutral under one screw. Photo 2 the aforementioned white ungrounded conductors in a raceway. Is the panel in photo 2 a subpanel or a service? If it's a service I can't see the main bonding jumper between the neutral and the enclosure. Many unsecured cables.

each panel is wired as a seperate service panel. Unless ther is a disconnect in the box above panel, first time I've seen this.

I noted EGC and neutral/one screw, loose cables, and rust in panel. Regarding age of panel, defects I've posted, would you as an electrician warrant for further inspection and repair?

[Sean Fogarty]

My trester, which is an ideal brand, occasionally will show a weak ground light in this scenario. I can sometimes wiggle loose plugs and the light will fade in and out.
Other times I actually had a faint light, and when I removed the outlet from curiosity, found that the box itself was causing the light to come on very dim. There was no grounding wire, but the metal box was providing the tester with a faint source of ground.

[Christopher Currins]

Originally Posted by jpope

Very unlikely.

Thanks, that was I'm thinking. I noticed a few EGC's at panel 2, none in panel 1. Home built in 1969, original service. With defects I've posted would you recommend replace/repair by an electrical contractor?

[Robert Meier]

Originally Posted by ccurrins

each panel is wired as a seperate service panel. Unless ther is a disconnect in the box above panel, first time I've seen this.

I noted EGC and neutral/one screw, loose cables, and rust in panel. Regarding age of panel, defects I've posted, would you as an electrician warrant for further inspection and repair?

Wow, after looking at the new photo's I would say that this service is a nightmare.