Another Grounding bonding question

I have a question on this one. The disconnect is at the meter on the exterior of the home. There is a 4 wire feed from the disconnect to the main panel. The grounds and neutrals are separated and the bond screw is out. What I don’t understand is the effect of separating the ground wires and neutral wires on separate buses when the bare aluminum (4th wire in feed) is attached right beside the neutral on what looks like the same bar. Would the bare aluminum need to be on the ground bus on the left side of the panel.

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Yes, that is incorrect.
The main pic is blurry, but it looks like the two bus bars are connected permanently with the horizontal bar.

If those bars cannot be separated, then there needs to be additional grounding bars attached directly to the panel, along with the bare wire (EGC)

If the bars can be separated, than the grounding bus will still need the bonding screw as well

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Thanks Daniel, I don’t know why the main photo blurred. Here is a better photo of what I’m looking at. I don’t see how they can be separated.

I don’t even see that there is a grounding bus in the panel. Both busses are separated from the enclosure, and I don’t think there was a place for a bond screw on the left bus (which has the ground wires)

Thanks Scott, that’s a handy diagram for sure. Do you know a source of different scenarios? (Meter on a pole, disconnect at the pole, detached buildings etc)

They can both be floating off the panel, as long as one of them can be separated, and still have a bonding screw. If not, they should have attached a bar directly to the panel at these screw holes. Install does not appear to be done by a licensed electrician.

Is the left side ground bus definitely connected to the cross bar at the top? None of your pictures show that to be the case (bad angles).

If not, the bare aluminum ground conductor could just be moved to the left side ground bar.
Would still need to bond the panel to the ground bar, if that is not done already.

The bars built into the Square D panel are neutral bars and cannot be separated into ground and neutral. Auxiliary ground bars should have been added. The grounding conductor next to the neutral is incorrect.

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Thanks for the explanation Jim, I didn’t see a way to separate them. The Realtors around here always blow a gasket when I bring up something like this so it’s good to have info from the forum. So outside the scope, what would this cause. Would there be some voltage on the ground wires? I have a subpanel in my house with a four wire feed and the same setup and there is 4.5 volts on the ground wires.

Yes, it can allow objectionable current to flow throughout all the grounding wires, and could lead to a shock hazard at the outlets/appliances

That’s some pretty ugly electrical work. The bundle of NM cables is not permitted to be run through a single terminal adapter

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Check out the subpanel in the garage, they didn’t run four wires to it. Just stuck the ground wire in the neutral bus. How dangerous is the wiring in this house?

This panel is dangerous. They’re using the bare EGC as the neutral, there is no EGC with the feeder and the bus is not properly bonded to the enclosure meaning that the enclosure could potentially become energized. Depending on the calculated load it might be better to convert this to a 120 volt panel using the 3-wire feeder.


Interesting thought that I never thought of for future reference.
Thanks for the post Robert!

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There is nothing correct in that panel, whoever installed it did not know what they doing.