Re: Newbie (ignorant) tech question

On Fri, 5 Jan 2007 11:06:15 -0700, "Dan Beck"
<biscuitbecks@*nospam*cableone.net> wrote:

Hello all,

I have a constant duty AC (28 VAC) motor that runs in one of my pinball
machines. I wish to control power to the motor such that it only runs
during gameplay. There are "recipe" circuits that do this for DC motors
that do the same thing, in pinball machines. The heart of this "recipe"
circuit is a TIP125 transistor. Will this transistor work in an AC voltage
circuit?, Or, is control of AC motors more complicated than I am
anticipating?

Thank you for any and all responses!

Regards,
Dan

No, you don't typically use a transistor to switch AC - it can be done
but it is perverse.

Use a relay powered from some other circuit that will provide a
voltage to the coil of the relay when you want the motor to turn on.

The voltage you have and relay coil voltage must be compatible.

Some Solid State Relays will switch 24 VAC to 240 VAC and only require
a DC voltage of 3.5 to 12 for the "coil"

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