Main distribution panel of a home built in 1974. Need help with a narrative about items in the attached photo?
There were grounded (neutral) conductors that were not individually terminated. You should have each grounded conductor separated and terminated individually.
Twin taps not allowed .one wire only under each screw .
That includes the large Aluminum and copper wire One wire only.
This needs to be repaired by a qualified person .
There were neutral and ground wires under the same screw. This is not allowed under the National Electric Code. Neutral wires should be only one wire per screw, unless the box is specifically listed and labeled for such use. Copper and aluminum wires should never be be under the same screw, as they can fuse together. We recommend repair by a licensed electrician.
There are multiple lugs with more than one wire. Current standard building practices require no more than 1 wire be secured under any lug screw. This can be a possible hazard due to unequal expansion and contraction of the wires under a single screw causing a loose fitting.
Recommend a qualified electrical contractor fully evaluate the panel for repair.
There were grounded (neutral) conductors that were not individually terminated. You should have the grounded conductors separated and terminated individually.
Scott & Roy, are double tapped grounding conductors not allowed? I thought NEC 408.41 only applied to grounded conductors and manufacturers determined any allowable doubling of grounding conductors(neutrals). Any help would be appreciated.
EGC’s can be doubled, even tripled under the proper conditions. The panel listing must allow for it, and the conductors must be of all the same gauge and material (AL or CU).
CU and AL are not allowed to terminate under the same terminal, unless that terminal is specifically listed for such a connection.
Grounds and neutrals are not allowed to share a termination point, although you will find that it was a pretty common practice in the 70’s and 80’s.
[FONT=Comic Sans MS]I use something like this[/FONT]
[FONT=Comic Sans MS]Neutral (white wire) and ground wires (bare wire) are connected together on a single lug. Neutrals must always have single connection. Refer to a qualified electrical contractor to make corrective repair.[/FONT]