I have an AC motor that is says its reversible (and has 4 wires). I wanted to know how to power these types of AC motors, I have a capacitor I borrowed from an old food processor. I figured I should absolutely know how to power it before attaching 120vAC to anything. It has wires: white, yellow, black, and blue in that order.

 

Looks like a PSC motor, record the resistance between the conductors, most likely 2 coils with the same resistance.
Max.

 

Looks like a PSC motor, record the resistance between the conductors, most likely 2 coils with the same resistance.
Max.

That's the funny thing. I did a quick test and it says all of them are connected to all of them. Does that mean it's broken?

 

Ok, I measured the resistance between them anyway.
here you go:

blue - black = 9.5 Ω
blue - yellow = 9.5 Ω
blue - white = 3.0 Ω
black - white = 6.5 Ω
yellow - white = 6.5 Ω
yellow - black = 13.5 Ω

That's what the multimeter says, anyway. I hope you can make some sense of it. _-'(how, in general, do you connect this type of motor?)

 

What was the original use for the motor?
Max.

 

I'm having trouble positioning the blue.
But you could try hooking the capacitor across the black and yellow wires.
Feed active to white.
Neutral to black for one direction, yellow for other direction.

Just in testing with no load, run a 100W lamp in series to help prevent smoke

 

What was the original use for the motor?
Max.

OH! sorry I forgot to mention that it was a dishwasher motor. But I tried looking up the
model number: s62nxjdn-7170 (all caps). didn't get much

I'm having trouble positioning the blue.
But you could try hooking the capacitor across the black and yellow wires.
Feed active to white.
Neutral to black for one direction, yellow for other direction.

Just in testing with no load, run a 100W lamp in series to help prevent smoke

I'm sorry I don't have much experience with AC (that's why I made this. so that I might learn about AC motors). Is it possible this may damage the motor or is it sure? And what do you mean by "100 watt lamp?"

 

Just an old fashioned tungsten filament lamp.

Les.

 

OH! sorry I forgot to mention that it was a dishwasher motor. But I tried looking up the
model number: s62nxjdn-7170 (all caps). didn't get much

A dishwasher motor only has two functions, circulation and drain pump usually, so for all those connections I am wondering if this is a 120v/240v motor.
What was the make/model No. of the D.W.?
Max.

 

Just an old fashioned tungsten filament lamp.

Les.

Like a light bulb? (how do I connect that safely? do I have to buy a socket?)

A dishwasher motor only has two functions, circulation and drain pump usually, so for all those connections I am wondering if this is a 120v/240v motor.
What was the make/model No. of the D.W.?
Max.

I know it's a really old whirlpool (but we don't have it anymore)

here is what the label on the motor says in full:
_____________________
FSP® |part no. 303574 |

pump
assy
no. 3367440 ®ЯU E22922
_____________________
(second half)
MODEL S62NxJDN-7170
HP. 1/3 VOLTS 120 PH. 1
HZ. 60 RPM 3450 AMPS 5.3
CL. B 40°C REVERSIBLE
THERMALLY PROTECTED

MFG. DATE
8 0 7 A 5

But is it safe to try and power it?

 

But is it safe to try and power it?

It is a question of trying different combinations, it appears to be a simple PSC motor but these typically only have 3 connections and are reversable.
Max.

 

I saw this video:

but I didn't quite understand it and it wouldn't have helped if I didn't know what wires where what.

Now the question is, would connecting it wrong damage it?

 

Now the question is, would connecting it wrong damage it?

That is why an incandescent lamp is placed in line with the power for a start. It limits the current to help prevent smoke.
Even a 40W one will probably work ok with no load on the motor.

 

I see what looks like a thermal cutout in the picture. That device is intended to disconnect power if the motor overheats. So a close examination should show which wire is connected to one side of that device. That wire would be the direct power connection.
AND a suggestion to locating the intended circuit, which is to look on line for a circuit of that model dishwasher. That will show you how it was intended to work.

 

I see what looks like a thermal cutout in the picture. That device is intended to disconnect power if the motor overheats. So a close examination should show which wire is connected to one side of that device. That wire would be the direct power connection.
AND a suggestion to locating the intended circuit, which is to look on line for a circuit of that model dishwasher. That will show you how it was intended to work.

You're right! I thought that all the wires just disappeared into the other side but now I see that the blue one went under and connected to the little metal box thingie staped to the side of the coil. so that means the blue wire is not needed?

That is why an incandescent lamp is placed in line with the power for a start. It limits the current to help prevent smoke.
Even a 40W one will probably work ok with no load on the motor.

I connected a few other 120v AC motors that worked fine without anything. but I connected one between the wrong two wires and it blew. would that prevent damage from that or is it just for when I am planing long term use?

 

I connected a few other 120v AC motors that worked fine without anything. but I connected one between the wrong two wires and it blew. would that prevent damage from that or is it just for when I am planing long term use?

The lamp in series is for testing. It is an old trick used when fixing switch mod power supplies amongst other things. The idea is if excessive current flows, the lamp lights and limits the current. Incandescent lamps are very good for this as when they are cold, the resistance is lower. But as they heat up, the resistance increases so dropping the current available to the device under test.

 

It is a question of trying different combinations,

Now I tried all the combinations between the wires (not including the blue one) and the result...
Well, all that it did was make a loud buzzing noise and vibrate a little. didn't even try to turn.
does that mean its broken?

dendad,
It seems like a cool trick but unless I can find a way to connect it safely, I don't really feel comfortable running 120v AC with sticking out wires. if I have to I will figure somthing out.

 

Now I tried all the combinations between the wires (not including the blue one) and the result...
Well, all that it did was make a loud buzzing noise and vibrate a little. didn't even try to turn.
does that mean its broken?

Did you include the capacitor?

 

Just an old fashioned tungsten filament lamp.

Les.

What about inrush?

 

What about inrush?

The lamp will flash then dim if all is ok. And, the motor is run with no load so the expected current is lower.
A larger wattage lamp can be tried to increase the current. That is why I have a power board with a lamp socket in line so different lamp wattages can be used.
It is a good idea to keep a few tungsten incandescent lamps aside as they are getting harder to find.