# Trying to Wire a Washing Motor To Power a Grain Mill

1. Sep 19, 2015

### hawaiibrewer

Aloha, I'm new here and stumbled across this site in my attempt to salvage a whirlpool washer motor to repurpose as a motor to grind barley to make my beer. Until now, I just used a hand crank and decided it's time to modernize. I just salvaged a nice looking, 3 speed, 1/2 hp motor from a recycle place here in Hawaii and have been trying to get it to run. I actually succeeded in getting it to run, but within 15-20 seconds, it gets too hot to touch, so I know something is wrong with my wiring. Until I did further reading on this forum, I was unaware that I probably should have looked for a capacitor near the motor. There was not one attached to the motor. The motor did start without needing a spin of the shaft, so I thought maybe a capacitor wasn't needed. I' ll try to attach an image of the motor and 6 wires coming off of it. I also have the wire harness that has a grey wire which attaches separately to the motor via a small, black object connected to a white wire that disappears into the motor. I hate to give up on trying to use what seems to be a good motor....and at this time, its more about making it work versus trying to save a few dollars. Thanks for any help with this...I hope this forum is still active. The motor is Whirlpool part number 852995. Aloha, Paul

2. Sep 19, 2015

### hawaiibrewer

3. Sep 19, 2015

### Staff: Mentor

Welcome to PF.

Questions of wiring AC power circuits should be directed to a licensed electrician. A mistake or misunderstanding could result in injury or death. Indeed, you already had a close call when the motor got too hot to touch. PF rules do not allow us to discuss dangerous topics on this very public forum.

4. Sep 19, 2015

### Merlin3189

5. Sep 19, 2015

### Staff: Mentor

If you could find a wiring diagram for the washing machine that motor came out of, you'd know how the motor is supposed to be wired. Chances are you'll find one online if you keep looking.

Be aware that if the motor became too hot to touch, it may not be a perfectly good motor any more - you may have killed it.

6. Sep 19, 2015

### jim hardy

I'll have something for you later today.
I also owe Tim9000 help with his inductor

and am in the middle of putting siding on the house..

Whirlpools i've found all use the same speed switch but the wire colors vary somewhat depending if it's from a Sears, Whirlpool, Maytag or KitchenAid. I just did a GE too, their switch is different ...

But there's basic physics that dictates what any manufacturer had to do to make their motor start and run. From there it's obvious why they wired it the way they did.
Once you've figured out your first one it's intuitive.

I'd recommend you do your work from a GFCI outlet, and by code any outdoor or garage outlet should be GFCI. So should anything in bathroom or near kitchen sink - perhaps your wife would let you run an extension cord? Then you are very well protected.
I made myself a cord with GFCI receptacle. I had an old cord with a bad end, just nailed an electrical box to a plank installed the GFC! and wired the old cord to it.

Meantime can you insert a photo of the motor? Is it two speeds or three?

7. Sep 19, 2015

### jim hardy

okay here goes...
That it started itself says something is wrong,
and that could be shorted turns in the motor
or it could be your wiring.

these are the important parts

You said it's a 3 speed motor.

Firstly this is a physics forum so a word on motors is in order.

This page shows the rotating magnetic field of a motor after it has started.....
http://www.ece.umn.edu/users/riaz/animations/sqmovies.html
sorry, cant post that image

Before it starts, Bm does not rotate just oscillates in the vertical plane. So the rotor does not know which way to turn.
That's because a vertically oscillating magnetic field can be represented as two uniform ones rotating in opposite directions
and the rotor is happy to follow either one after you nudge it in either direction.
That's key to motor theory - a rotating flux must have two components and their angle must not be 180 degrees. The start capacitor and its winding give you that phase shifted component , it's exact angle is not critical but somewhere around 90 degrees works best..

That's why there is a start winding, to provide rotation to Bm until the rotor has begun spinning. Once that happens it'll follow whichever component of Bm you picked and you can disconnect the start winding.

Okay, so a washing machine requires two windings to start and run, a run winding and a start winding.
The run winding is energized continually , the start winding only briefly, so the start winding is probably made from smaller wire.
If the motor is multispeed there'll be multiple run windings.

So let's draw a picture...

Pardon my crude schematic
get yourself a pencil and paper and draw one for your motor, arranged to suit your likes.

Those windings will be interconnected by switches so that you only have to apply power and the motor will go.
The Start-Run switch is the key to figuring out your motor.
To keep that switch simple and cheap to manufacture, not every wire will go through it.
Here's what Whirlpool does on that style motor:

All 3 run windings (at least in my Whirlpools) are tied together and that common point exits the motor through the thermal switch, which goes to the washer's white(neutral) wire.
Makes sense, the thermal should protect all the run windings..

Since the start-run switch is the key to understanding how they wired this motor, let's look at it...
Only one screw holds it in place and the cover slides off easily

The centrifugal switch moves the contacts UP when the motor is stopped, ready to start
and lets them DOWN when it is running. (oops said it backward first try)

Closer view? I'll number the terminals left to right..

OBSERVE TERMINAL 6 is a safety earth connection. The mounting screw ties it to the motor frame.
Remember that switch is now DOWN, in the RUN position.

With your ohmmeter you can now verify that all 3 run windings have a common connection to the white wire exiting the thermal device.
I'll wager you find continuity between 4, 7 and 9 which are the three run windings , and their common at 3.

So let us now identify the start winding.....
It is a safe bet that bottom contact controls the start winding because it's open in RUN (down)and closed in START(up).
So power to start winding comes in on 10, goes through contact up to 1, and into start winding's black wire,
but back out where ?
Find it with your ohmmeter ,
and i bet you a junkpile motor other end of start winding is that yellow wire on 5.(red on some motors)
So start winding power takes route 10-switch-1-black wire-yellow wire-5.

Now for run windings.....
think a moment... there's three of them.
Here's where the designers got clever with their switch......

Start winding must have same number of poles as whichever run winding is selected or else the motor will just buzz and get hot.
(Trust me for a moment - they always start on high speed. Proof later...)
Which means ,
IF you want to run at low speed
THEN the START-RUN switch must select that lower speed AFTER the motor has started.Okay, which contact does that ?
Hint : the only one left.

Remember the switch is UP to START , DOWN to run so it's shown in running position.
So, RUN power comes in on 8, through the speed switch and back out on either 4 or 2.
Since switch is UP to start, and start is always high speed, then 4 must be the high speed winding.
Were this a 2 speed motor with only one more run winding, that winding would be on 2 (and it is on my 2 speed Whirlpool)
but since this is a 3 speed motor with 3 run windings,
the choice of which low speed winding to use is made by another switch.
Those other two low speed windings are on 7 and 9
you will verify all the above with your ohmmeter of course.

The run windings' common goes to the thermal gizmo as mentioned earlier

so let's add these terminal numbers to our earlier sketch

Look how clever they were.
Start winding is isolated so we can select direction it'll run with an external switch
But - run winding common is brought to the switch , terminal 3, just to provide a point where designer can hook the start winding's return side. Note that routes start winding return through thermal for protection. But it lets designer swap directions easily with an external reversing switch.

Likewise we select between the two low speeds with an external switch.

White common wire from thermal on some motors lands on the switch, on others it does not...

Let's add the start capacitor..... and our switches.... and the safety earth to terminal 6...
wires you'll need are in yellow (and green)

I use wall switches from the hardware store, they're cheaper than small toggles. And they mount in handy boxes.
For high-low speed selectors 3-way light switches work fine, they're spdt

here's my 3 speed Whirlpool, one switch is ON OFF, other is fast-slow. I only wired up two of the 3 speeds.

Start capacitor seems not critical maybe 40 uf per horsepower. This is a 1/2 hp and it starts fine with a 20 uf motor run capacitor

All the above being said

If it runs okay both directions,
repeat for the low speed windings.

Last thing -
how do i know they always start on fast speed?
By experiment. I energized just the low speed winding and gave it a spin. It ran, but not fast enough to activate the centrifugal start-run switch.

I considered submitting an Insights on this, but since it isn't very academic it's offered as plain folks help.
Price a new 1/2 hp motor for a workshop project and you'll quickly appreciate the humble washing machine motor salvaged from a discard.
And it's written to teach a beginner how to figure it out next time .

old jim

Last edited: Sep 19, 2015
8. Sep 19, 2015

### meBigGuy

WOW, that was an incredible post, Jim. Should be preserved somewhere.
Way too practical for Physics Forum though. Pretty soon people are going to expect everyone to actually research topics and post real answers.

9. Sep 19, 2015

### jim hardy

Thanks MBG

my friends all now have better shop grinders and shop fans than we could afford to buy new.....

Maybe someone could improve my motor theory and get the post up to PF standards.

The GE motor had a simpler switch than the Whirlpool but my pictures were out of focus. These were taken with a friend's cellphone....

The principle is straightforward just there's too many permutations of the wires to guess at it.

So armed with basic understanding of how a motor works, anyone can peek inside the switch and figure out how to make it go.

Be aware - new washing machine motors are synthesized 3 phase field vector oriented computer controlled tech-shows
so stash away a few of these oldies. They're on the way out.

10. Sep 19, 2015

### meBigGuy

Awww --- and here I was thinking how cool it was that old jim had a cellphone that could take pictures. The post is way over PF standards.

11. Sep 20, 2015

### hawaiibrewer

Wow, fast response and very thorough for sure. Thanks Jim. I'll get out my meter tomorrow(Sunday) and do some playing around with the switch. I took the switch apart yesterday to get an idea of what was inside and saw the contacts but didn't put any meter across them since I really wasn't sure what I was looking at. Once I get the wiring sorted out and k ow its a good motor, I'll go (try) to buy a starting capacitor for the motor. In the mean time, I'll use the " manual" spin technique for starting it. I have all GFI in the garage, kitchen, bathroom and my home brewery so I typically use those when playing with electricity. Always keep a fire extinguisher on hand too. I appreciate the other comments about safety and hiring an electrician, but I won't learn anything and its not as fun as doing it yourself. I could buy a new motor on line( none available in my town in Hawaii), but that's the simple/easy solution. I've had zero luck posting photos or an avatar from my tablet...so I'll try from my pc tomorrow, but Jim's photos look just like what's sitting on my bench.
Aloha and thanks again,
Paul

12. Sep 20, 2015

Capacitor costs $6 at my local electrical supply place. They're in every junk airconditioner(fan run cap) or washing machine... I first give motors the sniff test, do they smell burnt? Are any windings charred or mechanically damaged(scrapes, gouges, cuts) ? My junkyard guys just throw them on a pile so bent shafts cracked frames and smashed switches are common. Before you apply power check to make sure no windings read continuity to motor frame. Have fun, and take pride in recycling a pretty darn good piece of machinery. UPLOAD button below & right will find pictures on my machine - try it with your tablet ? 13. Sep 20, 2015 ### hawaiibrewer I'm on my PC now and it seems to handle the pictures/avatar loading much better.....here is my motor that I'll be working on today thanks to your help....the wire harness from the washer is attached in the 2nd photo. Once I determine if the motor is good, I'll use the harness wiring to connect to my on/off switch. I happen to have a couple light switches that I removed from our house when I replaced them with ceiling fan speed switches. I already bought a junction box to hold the switch(s). I'll check our local AC/electrical supply store tomorrow to get a capacitor, I'm sure they'll have one. I'm sure the washer I salvaged the motor from had a capacitor but since it wasn't attached to the motor, I ignored looking for it. After looking at a Whirlpool wiring diagram for similar models, the capacitor wasn't located far from the motor....next motor I salvage I'll be more thorough. Oh by the way Jim, are clothes dryer motors worth salvaging? Seems to me they would mostly be all single speed, not as fast as a washer, and might be better suited for my use since I need about 200 rpm for optimum grain crushing for beer, My plan was to run the washer on low speed(850rpm) and then use pulleys to reduce it to about 200 rpm. Thanks again for your help and encouragement....I'm printing your prior response now to follow as I test my motor. Aloha, Paul 14. Sep 20, 2015 ### jim hardy good pictures. Yours looks just like mine only cleaner. Sounds fine. I don't know how much torque you need..... the motor might be better able to cool itself at high speed - notice those fins on end of rotor? They're a crude centrifugal fan to move air over the windings..... so try to keep your pulley options open. If you have an AC ammeter check running current against nameplate The few dryer motors i've looked at at were 230 volt(not handy) single speed (same as washer motor's high) and only 1/4 hp. They have a really small pulley to make the drum turn slowly, but it's that special grooved dryer belt.... I really recommend you draw a schematic and add colors of every wire. Yours look exactly same as mine. . One last word on the safety issue. Washing machine induction motors are benign, 1800 rpm is their maximun speed at 60 hz. Never use a vacuum cleaner motor for a home project. Vacuum cleaner motors are series wound universal motors, powerful, and capable of extreme RPM's in excess of 10,000. A typical ceramic grinding wheel will fly apart around 5000 RPM and embed pieces in the wall, ceiling , and spectators. If it's got brushes, leave it in the junkpile. That'd cut off an arm. Think safe. old jim 15. Sep 20, 2015 ### hawaiibrewer I was wondering about the lower speed torque and figured I'd just try it and see if it turned the mill. The rollers are small and the weight of the grain is pretty light. I hadn't thought about the cooling aspect. The grinding process only takes about 10-15 minutes, and increasing the large pulley size in order to use a higher speed is possible. Not being an electronic guy...more a mechanical guy, it seemed like what you were explaining is that I need to start the motor at a high speed(blue wire #4) before I can switch it to low speed(white with orange strip wire #9). I was trying to keep it simple and wire as attached......by the way, all windings checked out after using your guidance. Pics attached of my grain mill as I'd imagined and wiring diagram. For sure I'm aware of speed with motors and saw a You Tube of the exploding grinding wheel...caused a fatality. Thanks for being patient with me and walking me thru the motor wiring, I'm learning a lot and I guess that's part of the reason for the forum. Aloha, Paul 16. Sep 21, 2015 ### berkeman ### Staff: Mentor This thread is a little marginal safety-wise, but I'll allow it for now. I know Jim will report it if it goes on the wrong side of the "safety barrier". BTW, I may have missed it, but where are the fuse and switch being placed in all of this? What is the fuse rating? How is Earth ground connected to the metal body at the power inlet? 17. Sep 21, 2015 ### jim hardy Paul - you seem a practical sort... most mechanicals are... See my changes to your wiring sketch. Greg's right it oughta be fused (10 amps about right for 8 amp low speed winding) and be sure center ground prong on cord is tied to any metal that touches the motor or wiring. Congratulations on posting pictures, Above all keep this thing safe for any tiny fingers that might be in your household - belt guards, wiring covers etc. keep us posted. 18. Sep 21, 2015 ### jim hardy 19. Sep 21, 2015 ### hawaiibrewer Thanks for the image of your shop fan......maybe another project for me if I can scavange another motor. The sad thing here on this island is that nobody disassembles the "broken" appliances to salvage parts. They are crushed and sold as scrap waste......so my timing has to be when a new discarded appliance arrives before crushing. Once I get the thing working, I'll build a guard for the pulleys but I'll be the only one using it(64 yrs old) and no kids will ever see it. I'll ground it to the metal body via a tapped screw and use the 3 prong/wire cord I have. I'll use heat shrink tubing and wire nuts to cover any exposed wire not in the junction switch box.....I try to keep things safe. Ok, 9:30am, off to buy a capacitor and fuse link/wire.... Aloha.... Paul 20. Sep 21, 2015 ### jim hardy Maybe he'd set a couple aside for you - my salvage yard will do that. They have a bin for electric motors and transformers. Found a Tektronix 2211 Oscilloscope in it ... 30 cents a pound. I clamp the motor between wood blocks notched to fit , tighten with plumber's strap and carriage bolts. Thanks for the update - good luck ! Bonjour, y'all ! 21. Sep 21, 2015 ### dlgoff Very little needed to do that Jim. Just this: Well, the dang .gif motor looks fine in the preview. 22. Sep 21, 2015 ### jim hardy yes, that was frustrating. Computers are just that way. Thanks Don. 23. Sep 21, 2015 ### dlgoff Which part? The wires or the pullies? I guess I'm remembering a few weeks ago when my middle finger got to close to a moving belt. Still have finger, but belts needs replacing. True story. Safety should always be first priority and reevaluated in every task of a project. Get lax, loose a finger. 24. Sep 21, 2015 ### hawaiibrewer ....I found a capacitor, but took me 3 places before an electrical supply house had it....$11.00.....the "island tax" almost doubles much that we get here. Many on-line sellers won't even ship to Hawaii or Alaska....Oh well, the down side to island living. Found the fuse wiring, 20amp, at Walmart...much cheaper than any electrical supply place. I'll wire things up this afternoon and see how it goes...

Thanks again for all your help and hand holding.

Aloha,

Paul

25. Sep 21, 2015

### hawaiibrewer

Both parts of safety...wires will shock you, belts burn/cut you.......I'm used to moving belts since I have a drill press, band saw, and other power wood working tools....and remember all the industrial arts videos in Jr. High School of boards being kicked back via a table saw thru people and hair, loose clothing and ties being caught in belts/pulleys. Having been shocked many times while working around our house, I'm "sort of" used to electrical shocks and much to my wife's chagrin, have been known to change switches and outlets without throwing the circuit breaker.