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How do you connect multiple wires together for a harness? Answered

If you are creating an automotive type wire harness and need to connect the same ground to say six switches or relays, what's the best way to connect 6 short wires together to one longer wire that runs to GND or +?  I've tried multiple methods using soldering and butt connectors, but all have poor results.


The easiest way that I know, especially if you need environmental protection, is a 'bussed feedback receptacle'. That is what they're called in the Deutsch product line. I don't know if there are other names.


They would be brought back through the firewall to a suitable buss bar, running separate ground lines along with the local power and/or data lines, where large ground loops are unacceptable, or by using the chassis for a local ground for bulk loads that are insensitive to ground loop noise like electric window motors or other bulk loads with no onboard electronics. However, the use of local grounds as one might see in a 1960s car seems to be tapering off with the adherence to modern low noise techniques.


3 years ago

Pick a node and run each individual ground wire from the node.

What do you mean by node?

For instance, if I bring all six together, 6 16ga wires makes a large bulk about a 1/4 inch wide that won't fit into a spade. Or if I strip 3 inches of wire and stagger them every 1/2 inch, then I have 3 inches of inflexible soldered connections. None of which is very clean or desirable. Is there a connector or technique to bringing them together?

A node refers to a point on a wiring circuit where two or more circuit elements meet. http://en.wikipedia.org/wiki/Node_%28circuits%29

You have discovered the annoying reality of making a harness.

The 3 inches of wire may be your best bet, just pick it to end-up in a straight segment. Some time the wires may be resistance welded allowing for smaller joints and unlike solder seepage immediately flexible beyond the joint.

I am curious, that single ground wire had to start somewhere. I would use that start point as the ground node, that is why automotive fuse multiple spade lug expanders exist.

The one thing you DO-NOT want do is point to point wiring on a power bus wire.

Good wiring :)

The chassis (body) of a car is usually ground.

Most electrical items will be connected locally to a convenient nut/bolt and spade connector.