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hawk4611
Wiring a rheostat

How is a rheostat wired? I have no wiring diagram and have not wired one before. The rheostat has 2 black leads that arent marked any different from one another and it runs a fireplace fan.

kentvw
Re: Wiring a rheostat

It is wired no differently than a switch. The white (neutral) ties straight through to the motor. Incoming black or color (hot) ties to one black lead and the black or color (switch leg) goes to the other black lead and to the motor. Which black is which does not matter.

Blue RidgeParkway
Re: Wiring a rheostat
hawk4611 wrote:

How is a rheostat wired? I have no wiring diagram and have not wired one before. The rheostat has 2 black leads that arent marked any different from one another and it runs a fireplace fan.

assuming it is a true rheostat and not a jumped potentiometer, you'd need either the wiring diagram for the rheostat or an ohmeter to determine which pin connects to power and which to the universal motor in series and make sure that the current rating for the rheostat (amps) matches that of your motor or you could burn it out.

if it is a potentiometer being wired as a rheostat jumped or unjumped (three pins) then the outside unjumped pin is to power coming in and the center pin is to the motor. the other outside pin should be jumped to the center pin to assure contact and running if the sweep doesn't make full contact intermittantly in the turn since you're using for fireplace, but doesn't "have" to be. if it is actually a potentiometer you can use a voltmeter to verify a continuous circuit, which is safer for you.

a lot of modern fireplace fans and blower assemblies are powered by step down to low voltage power supplies. most fireplace fans warn against using a rheostat or potentiometer for speed control but being an electrician you know that. are you sure this is compatible?

JLMCDANIEL
Re: Wiring a rheostat

Ditto to what kent said.
Jack

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