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How to wire rotary switches? Answered

I have two rotary switches with 6 (six) positions each. To control ( 8 different model railroad tracks)...(12 volts on each track) The switches (from radio shack) have all seperate positions with (I assume) the power supply from the two terminals in the middle of the switch. Is there a way to identify the polarity of the leads or am I even connecting them properly??? HELLLPPP!!!!


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9 years ago

A rotary switch (generally) has One connection to the center post, and (in your case 6) additional posts radiating outward at equal angular distances from each other.
It may be identifiable by construction, or (as suggested above) by using a continuity test (meter or low-voltage circuit).
Either way, VERIFY what you have before using it in a circuit. I'd suggest model railroad websites for more directly applicable experience to your end use.

[try: http://www.atlasrr.com http://www.model-railroad-hobbyist.com or http://www.mrr.trains.com]
I don't see this as a fwd/rev selector, but as a track selector, with direction (i.e., polarity) determined elsewhere. They (or maybe I) will help you... they're quite friendly, too!


11 years ago

Two choices-look up the manufacturer to see if there is a wiring diagram available or try experimentally. If you want to experiment, get a ohm-meter and create a truth table (a graph with all the connections listed on each side and the switch positions on the top). Start moving the switch to different positions and chart which wires get connected (low or 0 ohms).