Electrical service ok or out of code

[Robert J Rolleston]

When I installed my 200amp electrical service a few years back the main panel and the three sub panels have a combined neutral and ground bar is this code or did the inspector overlook it.

[SQLit]

the service panel where the meter is should be the only place where the neutral and ground are on the same bar or electrically tied together. all of the sub panels should have a separate/isolated ground and neutral bars. Double check, other wise you dealing with a NEC violation and possibly a situation that could be dangerous in some situations.

[Art Todesco]

[zxcvbob]

Only the main panel should have the ground and neutral connected. All the sub panels should have separate ground and neutral bars, unless the subpanel is in a different building that has its own ground electrode. (And in that case, you treat the subpanel in a different building as a service entrance, with a main disconnect or no more than 6 switches.)

Best regards, Bob

[zxcvbob]

That is the "service panel", and its grounds and neutrals are allowed to be connected together. There should also be a large (#6 or #4) copper wire from that ground bar to your water meter and/or to the rebar in your concrete floor and/or a ground electrode hammered into the earth.

If you have additional breaker boxes or fuse boxes fed from the service panel, those usually need a separate ground and neutral bar but there are exceptions.

Bob

[SQLit]

My home was built in 1969. If you talking about the main panel where the meter is then your ok. It is still done that way today. If your talking about a subpanel away from the main panel/meter, check to see if you have (assuming 240/220volts single phase)

2 hot wires a neutral wire and a ground wire, which might be omitted if run in conduit. write back with specifics and I will try and help

[Robert J Rolleston]

[Robert J Rolleston]

[Tom Horne]

the main water pipe and also grounded to 2 grounding rods in the ground and the metal in the cement. The one 100amp in the garage is fed by 4 wires I was able to split it into a seperate ground neutral. There is one 150amp that is fed by

3 wires. If the 100amp panel with the current grounding is ok. I may do the same for the 150 amp panel. It is pretty much installed to power an electric tankless water heater that hasn't been installed yet. So the only thing I have wired into it are some 220 appliances an AC unit Heat Pump Water Heater and some electric heaters. all them only have three wire plugs. If I make the panel so it has a seperate ground and neutral is it possible to make the appliances work with a four wire plugs.

There is not enough information here to answer your questions. Are you talking about a 150 amp panel that is supplied by a feeder from your service equipment? If the answer is yes and all the loads in that panel are 240 volt then it may be wired correctly right now. A panel that does not contain any breakers rated at less than thirty amperes that require a neutral connection to the circuit is a power panel. Such a panel may not contain any neutral connections at all. The buss bars in that panel may all be bonded Equipment Grounding Conductor buss bars. If no loads requiring a neutral connection are supplied from that panel then there is no need for a forth wire to serve as the grounded current carrying conductor (neutral) for loads that don't exist.

-- Tom H

[Jeff Cochran]

The first question is how far away the sub panels are, but normally, only the service entrance has a bonded neutral and ground.

Jeff

[Robert J Rolleston]

[Jeff Cochran]

The reason I asked distance is that sub panels locate next to a main may not need to have a split ground/neutral. But at 50 feet, it's clearly a code violation. Best suggestion is to check with your local inspector.

Jeff

[anthony diodati]

Sure it does. The only time bonded neutral and grounds are allowed in a sub is if the sub is in a detached structure with no metal running between the two buildings, (water pipe,phone line,CATV line, etc.) And there in NO ground feeder run from the main. IOW you are only running 2 hots and a netural, All detached structures also require there own ground rod(s).

So a sub panle located next to a main needs 4 wires from the main.

2 Hots, a neutral, and a ground. The neutral in the sub is isolated from the box and not tied into the ground buss.

Branch circuits,(from the sub) neutral wires to neutral buss, ground wires to ground buss.

Thanks, Tony D.

[Robert J Rolleston]

[Tom Horne]

Not sure if that makes a difference

Does the house have one feeder supplying two panels or two feeders? Any given building is supposed to have a single feeder or branch circuit supplying it. The exceptions to that rule do not generally apply to residential property.

-- Tom