I just performed an inspection on a condo built in 1972. The main electrical panel had no branch circuit ground wires visible inside the panel. The panel label was missing. The main water supply pipe served as the grounding electrode under the panel. The outlets inside are “three prong” and show grounded (except one room shows “open ground”). I’m not sure if I missed the wires bundled somewhere outside of the panel or this may have been allowed at that time? All the GFCI’s worked near six feet of a plumbing source as well. Any advise please. Thank you
What was the wiring method? Looks like conduit. Metallic conduit would not need a separate EGC.
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As jim said, it could have metal conduit, that can serve as a ground. Did you open a receptacle and look inside? That should always be done on an older home
3 possible scenarios:
- Either there is metal conduit acting as grounding. (If this is the case, there should still be a grounding wire connected to the metal box from each receptacle)
- Panel was moved, and there is a junction box hidden inside the wall or attic where they spliced all the wiring to extend it. And the original wiring had no grounding conductors**
(this looks like it is likely the case, because all those circuit wires are colored)-these are not the conductors that are run throughout the home. (This is also a problem if its hidden) - Original wiring had no grounds, and they “bootlegged” every single receptacle (Ive seen this done before)
option 2 and 3 are big problems, but the only way to know is to look inside the receptacles
Update: I just realized you said 1972, which likely does not have the older 2-conductor wiring, but it could still have been moved, and wiring extended, maybe they clustered all the grounds together, instead of running back to panel (also a problem)
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Yes, next time i will have to open the receptacle but I’m going to say they need further evaluation along with the “open ground” receptacles
Curious, do you have a pic further back? Where do those conductors go at each end?
I would point out that it appears the wiring was extended, and there is likely a junction box that is covered up. Was there a solar or generator hookup? That is the only other time you will generally see these colored conductors like that
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No solar or generator hookups as far as i could see.
Different colored conductors would be common in a conduit system.
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Cameron,
You have probably heard this before, but the easiest way to determine if the EGC is done through the conduit, and metal receptacle boxes, is to loosen the receptacle from the box, and see if the tester still shows grounded. IF, you are comfortable doing this with a live receptacle, of course. JUST dont let the side of the recep hit the metal box!!!
You would need to identify the raceway type to know if it actually qualifies as an equipment grounding conductor. Self-grounding receptacles would not require a bonding jumper to the box.
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