Submersible pump wires identification

[Gassan]

Hi All,

I got a three phase submersible pump that I have to test by putting it into the mains. I'm afraid to test it because I'm not really sure whether it's a three phase or a single phase motor.

There are six leads. The internal connections are not visible because they are within the enclosure. I don't want to disassemble it just to see the connections as doing so might lead to risk of water leakage in the future.

Three of those leads are interconnected. They have continuity and there are around 3.5 ohms between each of the leads. The colors of the these wires are red, white and black.

The rest of the three leads don't have any connection between each other. One of them, a green wire, for sure is the earth. It has continuity with the body of the pump.

The remaining two leads are white in color. As mentioned, they don't have continuity with each other and any of the other wires as well. This is what made me worry. I couldn't figure out what could be the purpose of these wires. Could it be a switch connection? Could it be for some kind of motor control? I don't know.

Since the resistance between each of the interconnected leads are about the same, I guess they are coming from three coils of an induction motor. If the motor is single phase capacitor start, induction run

type, then I expect the resistance between the leads to have different values.

That's as far as I can describe my problem. I took two photos of the actual thing but couldn't attach them because the file size was too large.

Hope someone would pop up with a brilliant solution.

[amyk]

More information about the make/model of the pump itself?

You can resize the photos and upload them.

[DTJ]

The remaining two leads are white in color. As mentioned, they don't have continuity with each other and any of the other wires as well. This is what made me worry. I couldn't figure out what could be the purpose of these wires. Could it be a switch connection? Could it be for some kind of motor control? I don't know.

Just a guess - perhaps the two white wires go to a pressure switch or other flow sensing switch (electrodes??) to enable prevention of dry running of the pump.

[Gassan]

Thanks.

I've talked to someone and he also came to a similar conclusion. Hr said that it should be a thermal switch which would help to prevent the motor from overheating.

[Gassan]

The pump is very old. I don't have any of its documents. The name plate of the motor also couldn't be found.

[beanflying]

Post up a photo. Industrial pumps was my 'real job' when I had one I might be able to ID what it is.

Generally all wiring and control of 3 phase submersibles was above ground and in a cabinet. To that end the six wires will likely be used as part of a Star Delta Starter.