Grounding wire jumped to adjacent panel in 2 family

I’ve seen this a few times in multi-family buildings with separate electrical services, where a grounding wire is jumped from one panel to another, to which the main grounding electrode(s) is/are connected.

This seems improper for the same reason a shared neutral and grounding bus bar would be improper for a sub-panel, and that the panel without the dedicated grounding electrode should either having a floating neutral or dedicated grounding electrode of its own.

Am I correct about this, or is such wiring perfectly acceptable?

You need to better identify the function of this ground wire. Is it part of the GEC or EGC?

Post pics of both panels with full view. Your first pic is also low resolution and hard to see.

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The grounding wire on top of the pic is the jumper from the right panel grounding/neutral bus bar to that of the left panel.

Unfortunately the better pics are on my phone, and I’m on the computer here, so it would be difficult to get the pics over, since I’m working up the report on the phone.

The right panel is grounded like a typical main panel, and the grounding wire for the left panel is jumped from the bonded neutral/grounding bus bar of the right panel. Both are otherwise wired as typical for main panels.

If you have 2 service panels (2 meters), that is a GEC and used to be a way old panels were wired. However, it is not the correct way to extend a GEC. There are several options to do it, I would just defer to an electrician to correct it to improve safety.

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Thanks for the reply that is in plain English, and not a code reference I do not have time to look up, Simon. I did not think it was correct by modern standards on account of too much potential for “crosstalk” between the grounding and neutral wires within the systems, stating it very simply.

There is no crosstalk issues between the two services because they are required to be connected to the same GES which ultimately connects them together anyway. The issue is the method that is being used here to connect each panel to the GES. It is common to use a single GEC and tap off to each panel.

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