Repurposing an old blower motor for a grain mill

This newsgroup has been very good with these kind of questions, even if maybe they'd work better in an HVAC repair group or the homebrewing newsgroup. I have a grain mill for crushing malt for homebrewing. The handle method is a pain in the but, and a lot of folks end up motorizing their mills. In my case, I asked the HVAC folks that had done a lot of work on my house for an old motor if they come across one. I've got one here now and I'm trying to make sense of it before I start trying to hook it up to the mill.

I think they were proud of themselves when they arrived with this metal enclosure with the motor and everything, which was fine by me. I had asked for a motor that works at 110V, and that's what they said they pulled. I did test it with a switch up to wall power, and it seemed to work--despite tripping the breaker when I turned off the switch. That was because methinks I botched that wiring.

So it is a 1/2HP, 1020RPM motor. Reading the side here, I see "V200-230." So is this actually a 220V motor? I'm not so sure because I see three jumpers labelled A through C:

A: LO B: MED C: HI

Which one I pick works in conjunction with the black contact to give me my line voltage. So does this mean I have some flexibility in voltage? It was connected to 'A' originally, and I haven't tried messing with it. If this somehow lets me using 110V, then what effect will this have on the horsepower and the rpm? I have yellow and black lines going to a start capacitor rated 20.00/370.

It is a thermally protected motor and there's a note "CONT AIR OVER" which implies to me it normally would be cooled by the blower fins. I have to take that thing off to work this thing, so I'm wondering how long I might reasonably expect to run the motor before it trips the protection. I'd probably only need to run the motor 5 minutes to crush my grain, if that helps.

Reply to
adam.preble
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A motor from a clothes dryer might be more suitable.

Reply to
beecrofter

snipped-for-privacy@gmail.com wrote: ...

I'd guess the L/M/H are multi-speed contacts for an HVAC-application motor. The voltage rating certainly makes it appear it's rated for 200V.

My suggestion on connections would be to ask the folks you got it from for some guidance.

On the cooling, it'll probably manage a few minutes at a time w/o cooling anyway, although the load of a mill compared to that of an HVAC fan may be significantly higher. What about figuring out an arrangement to extend the shaft, perhaps?

Would have to agree w/ the other responder it might not be the most suitable choice for the job, but may get it to work. You'll need to gear it down quite a lot if the mill is designed for hand cranking unless it really does have intentions for being powered otherwise the bearings and all may not be up to the speed, either.

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Reply to
dpb

So shouldn't it fail if I'm using 110V? Maybe it can take the lower voltage. I have to wonder what that does to the motor's speed and power. Is there a way to determine what affect the contacts would have on the speed?

I guess I can look up the model information later when I'm in front of the motor again.

They said they pulled it from a 110V source, and that's about all they know. They had removed it from the housing and all from an old unit, so they hadn't read any information on it.

I can try to load it with something just to see how well it does. I'll have to mount it to something first though.

It's a standard thing to use some cheaves on this, at a 10:1 ratio even. Running the mill too fast will pulverize the grain, which isn't desired. A rough calculation is to get the mill to 150rpm. That part isn't a big concern compared to figuring out what rpm I'll get out of the motor in the first place, as well as what little surprises might await me when using the motor.

Reply to
adam.preble

Maybe they made a mistake/forgot?

Who said it came from a residential furnace? I'd guess from the other markings there's a good likelihood it's a dual voltage but that's as much conjecture as all the rest here w/ no further actual data.

Yep, that part seems pretty certain.

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Reply to
dpb

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