Practical Boat Owner

Understanding electrics: switches and relays

Switches allow a circuit to be ‘made’ or ‘broken’ so that a light, motor or whatever can be activated or isolated.

A switch has at least one pair of contacts that can be made or broken but it can be much more complicated. It can make or break several circuits at a time, or can be made to switch between one or more circuits, either individually or in unison.

Obviously the DPDT (double pole, double throw)

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