Connecting an electric motor with capacitors from a pumping station

Vitaly asks:

Hello everyone reading. I decided to make a sharpener from the engine from the pumping station. 600 watt motor. The kit included a 6 uF capacitor, for necessary reasons I completely disassembled the terminal box and unsoldered all the wires, but now I don’t remember how to put it back together.

Three wires come out of the engine - purple, red, gray + zero from the body. To which wires should the 220 plug and the capacitor be hooked? I have already tried to link 220 to purple and gray, in addition to the gray, I started up a capacitor and closed the circuit on red. The engine starts, but it gets very hot from the first minutes. They advised to remove the capacitor.

Removed. After three minutes of work on XX, the engine is barely warm.

Hello! The colors of the wires, unfortunately, do not say anything, measure the resistance between the wires. The working winding will have less resistance, and the starting winding will have more.

That is, make 3 measurements between different wires, for example:

1 and 2 wires - 15 ohms;

1 and 3 - 5 ohms;

2 and 3 - 20 ohms.

So 1 wire is common, 3 is the end of the working winding, and 2 is the end of the starting one. The wires between which the resistance is at most are the edges of the windings.

You connect zero to the common wire, the phase to the one with the lower resistance, and the phase through the capacitor to the starting winding. This is briefly.

According to your connection, the moment is not entirely clear "in addition to the gray, I started up the capacitor and closed the circuit on the red" - what have you closed? Phase? After the start-up, was it turned off or was it left?

But in general there are different motors, in some you need a capacitor for starting, in some for work and without a capacitor, it will not work normally. What kind of engine you have is unknown.

But since you have it warmed up when working with a capacitor - maybe he was only needed for starting, then there were some other relays or special start buttons that connected the capacitor only at start-up.

If for a sharpener - you can do without capacitors at all and leave, connect only 2 wires on which it will work better, but then when starting, you may have to push the shaft with your hand.

Maybe I will answer something else if you send photos of the terminal block and engine nameplates. I can also advise you to look for instructions from the pumping station - perhaps there was an initial connection diagram.

Also read this article, maybe it will help: https://samelectrik.ru/kondensatornyj-elektrodvigatel.html