One of the most common issues we see in electrical panels is “Double Taps”, or quite simply, 2 wires under the same screw/lug. So the question is, why is this a big deal?

In the immediate, here and now sense, it isn’t an urgent repair requirement, but it’s still wrong, and a safety hazard. Here’s why:

The natural expansion and contraction of the copper wire as it heats and cools. When current flows through a wire, it heats and expands. When current flow stops the wire cools and contracts. Double tapped neutrals or breakers can expand and contract enough to the point where the connection becomes loose. The loose connection could overheat and cause a fire.

Canadian electrical code reference for neutrals: Rule 4-026(d) stipulates that a neutral conductor be installed so that any neutral conductor may be disconnected without disconnecting any other neutral conductor.

Also, multiple neutral conductors in a single termination create a significant problem when the circuit needs to be isolated. In order to isolate the circuit, the branch breaker is turned off and the neutral is disconnected by removing it from the terminal. If the terminal is shared with another circuit, the connection on the other (still energized) circuit will be loosened as well. Loosening of the second neutral (loss of neutral) under load is a safety hazard, and may establish an overvoltage condition on lighting and appliances if the neutral is part of a 120/240 Vac multi-wire branch circuit.

The repair is easy enough for an electrical contractor. They can install a new breaker and move one load line to it, or in the case of the neutral bar, move one of the neutral conductors to an available empty lug.