Electrical Bus Bar Questions

An electrical conductor, usually in the form of a metal piece, is used to connect two or more circuits in a panel or fuse box also is known as an electrical bus bar. Bus bars may be surrounded by insulation or is supported on insulators. They are sometimes connected to one another and to other electrical components by clamp, bolted or welded connections. Busways are long bus bars that have a protective cover. Bus bars are normally found inside panel boards or switchgear. Many times when one takes on a job to replace electrical bus bar connectors, they run into technical issues and may need to ask questions.

Listed below are a few questions answered by the Experts on problems related to bus bars.

Is this electrical bus bar wiring correct?

Case Details: The main bare ground cable is connected to the neutral bar in my panel. The heavy white cable is connected from the neutral bus to the ground bus and both neutral and ground circuit lines are connected to the neutral bus bar. A few circuit ground are connected to the ground bus bar.

It is all wired correctly. The white cable acts as a bonding jumper that will complete the connection for the neutrals and grounds in the panel. And you can have grounds and neutrals on the same bar as long as they are not terminated together in the same lug.

Can a ground bus bar in the breaker box become hot due to a short from a faulty switch?

Yes, it is quite possible for a short to cause the bar to heat up.

Can I replace a square d electric panels bus bar or do I need a whole new box?

Case details: There is no digital reading on the electric company meter, no light on in the circuit and o banging the meter, sparks and lights come on and off in the house and the meter. On testing the box, 62 volts on one side and 115 volts on the other side were recorded. All the circuit breakers have been replaced since the box is outside and water got to them and corroded the bus bars.

There could be a problem with the meter base because the power keeps switching on and off. This may be because the connections have corroded and become loose or due to a problem with the socket connections. To replace the bus bars, you should look for a complete interior which is the same make as the original one since individual parts are not sold separately. Also, as the responsibility to maintain the meter base and its connections belong to the homeowners, you would be expected to repair it instead of the electric company.

Have I wired this bus bar right?

Additional case details: It seems like the neutral bus bar has two different rows of white, green and bare copper wires attached. I connected the white and green conductors for my circuit to the bar but have not switched on the power supply to the circuit yet. The outside ground is attached to both the rows at the bottom of the box with straps. This is also where the ground wires and existing neutral terminate.

You should be okay since the ground and neutral wires are tied or bonded together at the first point of disconnecting on a service which would be your panel. It is essential that the box is grounded and that the neutrals are bonded to the ground because it would help to catch any transient voltage that would come through the neutrals. Based on what you have said, the wiring seems right and you shouldn’t face a problem.

Bus bars can become worn out over time and may need to be replaced. To replace a bus bar, first switch off the main breaker that powers the entire house. Then remove the electrical panel and expose the wiring inside. Get a tape and marker to label the wiring and, starting from the top of the bus bar, mark the wires numerically. Use a screwdriver to take off the wires from the bus bar. Unscrew the mounting screws at the bus bar ends and remove the bar. Check the orientation while doing this so that you can replace the new bar in the same way. Then, install the new bar firmly in the breaker box. Connect all the wires back by following the labelling and tighten all of them. Finally put the cover back on the panel and turn the mains back on. If you have trouble undertaking electrical work, consult an Expert to help you out.