1
\$\begingroup\$

I just took apart an old dishwasher for parts. The large motor I got from it seems to be an induction motor. It has 4 wires. Green, yellow, red, and blue. I know for a fact that the green one is ground, so it can be ignored. It also had a 15uF capacitor for the motor, but I'm not sure how it was connected. The dishwasher is at a different house so I can't look now, but if I need to know how the cap was connected I could look next time I'm there. How can I figure out how to wire this motor? In case this helps, it is model 5kcp122e1bx, but I can't find much info about it online.

I just measured the resistance between the leads. blue to red is 16 ohms, blue to yellow is 4 ohms and yellow to red is 20 ohms. 16+4 = 20, so that means there isnt really a winding between the yellow and red. This makes me pretty sure that blue is a common, red is main coil and yellow is a start coil. That is what I would have guessed just looking at the wire colors. But having a second differently sized start coil, wouldnt that usually mean that the motor is resistive start and doesnt use a capacitor? I guess I am wrong as i obviosly has a capacitor. So how do I wire it up? Thanks!

\$\endgroup\$
5
  • \$\begingroup\$ what was preventing you from making note of the wiring before you disconneced it? ... look for a wiring diagram label on the dishwasher \$\endgroup\$
    – jsotola
    May 16 '20 at 19:38
  • \$\begingroup\$ @jstola I can look at how it was connected in the dishwasher later. I just didn't think about that then. Also some of the wires go up to the control panel and I would need to take it apart even further to see where they connect to which I didn't wanna do. Also im assuming its not resistive start because of the cap, but if it is then I wouldnt be able to know that as it doesnt have a centrifugal switch. I dont know a lot about induction motors. \$\endgroup\$
    – Randomaker
    May 16 '20 at 19:56
  • \$\begingroup\$ So I cant without a lot of work, and it would be a while until I would get to look at it again since it is at a different house and I haven't been going there very often. \$\endgroup\$
    – Randomaker
    May 16 '20 at 20:57
  • \$\begingroup\$ Is the capacitor connected to the motor? Can you measure the resistance from each wire of each other wire? \$\endgroup\$ May 16 '20 at 21:15
  • \$\begingroup\$ @Charles Cowie please read the addition to the question for the resistance measurements. Not sure if you mean like the capacitor is physically mounted on the motor or connected to it with a wire currently. It was in a different location and not mounted on the motor, and it is not connected right now to the motor. I think the yellow wire may have been connected to one side of it, if I remember correctly, but not sure where the other side was connected. \$\endgroup\$
    – Randomaker
    May 16 '20 at 21:45
1
\$\begingroup\$

The motor is a permanent split capacitor (PSC) AKA capacitor-run motor. I believe it should be connected as shown below. It would be good to check the current and be ready to shut it off if the current is too high. The normal current should be marked on the washer, but that may include the built-in water heater. The current with and without the heater might be marked.

enter image description here

\$\endgroup\$
4
  • \$\begingroup\$ Thank you, that helps me a lot! Do you have any idea how many amps a motor like this would draw? \$\endgroup\$
    – Randomaker
    May 16 '20 at 22:11
  • \$\begingroup\$ I just looked up if a start or run winding is higher resistance, and I found that the start winding actually has higher resistance? Is that correct? Do I then need to switch the windings in your diagram? \$\endgroup\$
    – Randomaker
    May 16 '20 at 22:23
  • \$\begingroup\$ I am pretty sure that the capacitor is suppose to be connected all the time, so the capacitor winding is the auxiliary winding rater than the start winding. The impedance of the capacitor will be about 177 ohms, to the capacitor will limit the current more than the winding will. If it doesn't have any torque the way I suggested, try it the other way. Alternatively, wait until you have more information about the washer. I don't think the motor should take more than 3 amps or so at 120 volts, half that if it is a 240 volt motor. \$\endgroup\$ May 16 '20 at 22:39
  • \$\begingroup\$ Ok thanks, I will try it out! \$\endgroup\$
    – Randomaker
    May 16 '20 at 22:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.