120 volt sub-panel?

Sub-panel in detached garage fed with a #10 2 wire, no ground. Neutral isolated. Grounding electrode conductor is connected to a ground rod at garage. (With two 10 gauge conductors, which is wrong).

Question- Is there anyway to make this compliant as 120 volt panel without running a new 4-wire feed?

Such as disconnect the two hots at left lug and add a jumper?

Of course the GEC needs to be replaced with a 6 awg.

The 120V feed can be spliced and “Y’d” to eliminate the double tap and jumper, or half the breakers can be removed. Not sure why anyone would install a 120V like this when a 240V would have made much more sense.

The bonding screw needs to be removed from the neutral terminal.

Thanks Jeff.

It is a do-it-yourselfer. It’s a seller inspection. The owner wanted to know what needed to be done at house before he put it up for sale in a few months.

So the GEC at ground rod can take the place of 3-wire feed?

Not in Canada and I expect not in USA you can only have one ground in the system.
The ground has to go back to the original service ground at main panel.
You need four wires for 240 volt or if it can stay a 120 volt then you need one Green and one white and one Black

Three conductors can be H+H+N. The neutral should land on an isolated bus in downstream panels. (which it does in the panel I posted)

The EGC’s should terminate in the downstream panels, correct?

So for a 120 volt you would have Two conductors, H+N.

I know a 4-wire feed is what’s required today, but what I have was done a few years ago.


Does the NM cable go underground or into a slab in contact with the earth?

Underground in PVC.

Having said that there is no hope to repair the current installation. NM cable is not permitted in a raceway in the ground. The NM must be removed and the panel feeder rewired.

Thanks Robert. Much appreciated.