Anyone know a source for 21VAC power supply?

[ToV]

I had a microwave fail recently; I scavenged it for parts. There were a couple standard 115v fans that I have some thoughts for in brewing (the range exhaust fan and a fan that might be used to keep breaks down). The magnetron was salvaged in an attempt to be half of a DIY stick welder (sometime).

There there are the two 21 V AC 50/60 Hz motors that have 29.1/34.9 and 2.5/3 RPM. If I could find a cheap source for power supplies I was thinking about building them into a stirring mechanism. Or if anyone knows what has that kind of power supply I might be able to find one to scavenge.

 

[passedpawn]

Try sears direct parts. Look for your model (or one similar, find the exploded diagram, find the PS).

 

[ToV]

Try sears direct parts. Look for your model (or one similar, find the exploded diagram, find the PS).

Thanks for the tip.

I tried this route and didn't see anything labeled a "power supply", the link is http://www.searspartsdirect.com/par...2/0123370/G0312017/00001?blt=06&prst=&shdMod= There is also nothing resembling a power supply on the wiring diagram or when I gutted the microwave for that matter.

Part 60 and 100 are the 21VAC parts I have scavenged. Buying something akin to a microwave power supply, will probably blow any savings by taking a couple motors out of a non-functioning microwave.

 

[passedpawn]

Thanks for the tip.

I tried this route and didn't see anything labeled a "power supply", the link is http://www.searspartsdirect.com/par...2/0123370/G0312017/00001?blt=06&prst=&shdMod= There is also nothing resembling a power supply on the wiring diagram or when I gutted the microwave for that matter.

Part 60 and 100 are the 21VAC parts I have scavenged. Buying something akin to a microwave power supply, will probably blow any savings by taking a couple motors out of a non-functioning microwave.

Part 12, the PCB, has a transformer on it. So, it's probably where the 21VAC is created. Either replace that transformer or the entire PCB.

 

[Toymaker]

You have a little discrepancy in your motor information. Is it 21 VAC or is it 21VA? VAC is a measure of voltage and VA is a measure of power. VA is actually watts. Most motors will have a call out for current and voltage separately. Double check the label. It seems odd to me why they would step down motor voltage in a household device. Normally everything would be 120VAC including the motors. It would be cheaper to design something at normal line voltage. This will keep wire sizes down and decrease costs. If you look again those motors are probably 120VAC... BTW the RPM ratings are dual because of the 50 or 60 hz. 50 Hz will rotate slower.

 

[ToV]

Part 12, the PCB, has a transformer on it. So, it's probably where the 21VAC is created. Either replace that transformer or the entire PCB.

Thanks, that is what I feared. Its not worth it to me to buy a 150 dollar control board for a microwave to simply spin a motor. The board was the defective part of the only microwave as well. Now if I could scavenge a power supply off of a buddy with a electronic device or buy a item from some china knock off site, I might be in business.

You have a little discrepancy in your motor information. Is it 21 VAC or is it 21VA? VAC is a measure of voltage and VA is a measure of power. VA is actually watts. Most motors will have a call out for current and voltage separately. Double check the label. It seems odd to me why they would step down motor voltage in a household device. Normally everything would be 120VAC including the motors. It would be cheaper to design something at normal line voltage. This will keep wire sizes down and decrease costs. If you look again those motors are probably 120VAC... BTW the RPM ratings are dual because of the 50 or 60 hz. 50 Hz will rotate slower.

Thanks, I understand the 2 rating for Hz and speed. I was simply trying to provide as much information as possible.

From the Sears parts direct website, this is how the motors are stamped.

I will go back and change the original post I left out a "C".

 

[Monster Mash]

A 24vac power supply will work just fine.

 

[ToV]

A 24vac power supply will work just fine.

Thanks, I might be able to source one of those. If it doesn't work I am not really out anything.

 

[beaksnbeer]

Lowes/HD have cheap 24 volt transformers look by the doorbells

 

[passedpawn]

Lowes/HD have cheap 24 volt transformers look by the doorbells

That is a GREAT idea!

 

[ToV]

Lowes/HD have cheap 24 volt transformers look by the doorbells

Thanks, I'll look into it next time I am there, which seems to be about once a week these days.

 

[Hockeyman]

Furnace transformers are also 24VAC...

 

[beaksnbeer]

I rarely find furnace supplies at my local stores, mmmmm wonder why?