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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Tuppe on July 19, 2015, 05:40:29 pm

Title: What is this coil in AC speed controller?
Post by: Tuppe on July 19, 2015, 05:40:29 pm

Hello, I'm investigating this air conditioning fan speed controller unit, which appears to have interesting components.

I'm first year EE stundent and I have no clue what that huge coil and the "sensor"(or another coil?) inside it are supposed to be and how they work. Is is some sort of transformer?
Can someone give me tips on this one? I couldn't find such coil arrangement in any AC speed controller circuits.

Thank you!

Title: Re: What is this coil in AC speed controller?
Post by: DanielS on July 19, 2015, 06:31:38 pm

My guess is this is simply a single phase SCR control and the inductor is there to provide 0-180 degree trigger phase delay - essentially the same circuit as a filament lamp dimmer.

Title: Re: What is this coil in AC speed controller?
Post by: Tuppe on July 19, 2015, 10:17:35 pm

Quote from: DanielS on July 19, 2015, 06:31:38 pm

My guess is this is simply a single phase SCR control and the inductor is there to provide 0-180 degree trigger phase delay - essentially the same circuit as a filament lamp dimmer.

Thanks! What would be then that component in the middle of the coil?

I guess it's either a cap or a safety thermistor...?