By Ed Sherman
Marine Electrical Connections: Two Wires, One Crimp Terminal?
Sending more than one wire to the same terminal connector is OK, bearing in mind a few conditions.
Question: I was checking out the wiring on my boat recently and noticed that some of the connections behind my electrical panel have two wires going to one crimp terminal. (See my photo.) Based on electrical standards is this an OK installation or should it really be two separate terminals?
Answer: Good question. The short answer is that it is OK to do this. The longer answer has some caveats that are really quite important.
Crimp-type electrical connectors are sized to accept a certain “circular mil” area of wire. Also, the connectors are engineered to handle a certain amount of amperage. The amount of amperage is coordinated to this circular mil area, or maximum diameter of the wire(s) that get inserted into the connector before it gets crimped.
What is most important here, is that none of the individual strands of the conductor gets cut off or otherwise damaged when more than one wire is being fitted into the terminal. If two, three, or even four wires fit into the terminal without damage to the individual conductors, and the crimp can be made to withstands a good pull test, then it’s OK to do it. As I look at the photo you sent in, all seems well.
- Ed Sherman is a regular contributor to boats.com, as well as to Professional Boatbuilder and Cruising World, where he previously was electronics editor. He also is the curriculum director for the American Boat and Yacht Council. Previously, Ed was chairman of the Marine Technology Department at the New England Institute of Technology. Ed’s blog posts appear courtesy of his website, EdsBoatTips.