I am trying to figure out the easiest options for building a cake stand that rotates no more than 3 or 4 rpm. I have found microwave turntable motors that have the reuired specs on rpm but they have 21-24 vac on the labels. I am assuming you would need a transformer? I want to be able just to plug it in since I am really weak on my electronics knowledge. Can I use a different type of motor and build/buy something that will reduce the speed to what I want. I am open to suggestions.

 

You just need a transformer with 24V output. Connect the primary to mains, and the secondary to the motor.

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Dave Pusey.
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Most microwave turntable motors are mains voltage, actually I've never seen a 24v one.

 

If I use this https://www.addison-electronique.com...ducts_id=90427 what can I do to control the rpms?

Here is a link to the other motor I found: 21V Microwave Turntable Motor 2.5/3 RPM 3W GM-16-2F302 - eBay (item 350211119315 end time Jul-07-09 07:41:06 PDT)

 

Likewise, every one I've ever seen (and I've seen a LOT) has been mains voltage.

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The last microwave I took apart had the turntable motor wired in series with the fan motor.
Actually it wasn't in series, but wired off a tap in the fan motor windings, the neutral was tied in with the mains neutral.the motor was labled 21vac.

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gerty

 

A 24VAC wall wart rated at >150mA (or >3W) will work.

ken

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Ok,
While everyone else argues about a "standard" voltage for microwave oven turntable motors, Ill just keep myself busy actually answering the OPs ORIGINAL QUESTION

The one in the Addison Electronics listing, in the middle is 120vac, at the rpm you desire...sems to be a good choice, although its 5rpm, and you have specified 3 or 4... I dont think that 1 more rpm is gonna kill you as far as cake rotation goes.

you know me....helpful to the bitter end....
Christ, I hope this doesnt add any positive points to my standing...

AAAAHHH, Addison Electronics, absoutely wonderful parts shop in Montreal. One of the few where you can still get tv parts, and anything else electronic. one of the fe true "Surplus" electronics stores around. Their catalogue is autrocious, but man, you go there and i doubt that anyone here would leave without at least 100.00 in parts, and surplus. Ive ordered from that place since I was 9....(as he wipes a tear from the wrinkled corners of his eyes)

 

I always assume the worst case. e.g. a cream pie at a diameter of 15feet. Where would the cream go at 5rpm?

There are lots of motors out there for any desired voltage and any desired reduction, mostly industrial overproduction items, and therefor cheap to buy.

Boncuk

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