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I'm seeking advice on some 240v mot

I'm seeking advice on some 240v mot

I'm seeking advice on some 240v mot

I'm seeking advice on some 240v motors I have aquired from a firm that repairs treadmills. I would like to upload some photos of the ID plate and wiring as it enters the motor but am having trouble understanding how to upload photos.
Pictures tell the story better than words but until i learn how to upload photos I will describe the motor and explain what I want to do with it.
It is a Lafert type AMI 90L/A4 with a 6 pin plug. One wire earths to the casing and 5 disappear into the motor. 2 yellows a black red and white.
I just want to motor to spin in one direction with maybe a speed controller at some stage.
Many thanks in advance

RE: I'm seeking advice on some 240v mot

It appears that what you have is a 3 phase motor designed for use with an Inverter, it MIGHT be 2 speed, hard to tell. Why there would be 5 connection wires for a 2 speed motor, I don't know, it should be 6, or 3. So what I suspect is that it needs 3 power connections, meaning it is NOT a 2 speed motor, and the other two wires (likely the yellow ones) are an embedded Thermistor used to sense the motor temperature.

"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: I'm seeking advice on some 240v mot


I think I've managed to upload my photos. The motor does have 6 wires, 1 connects to the casing and 5 disappear into the motor.

RE: I'm seeking advice on some 240v mot

Three phase connections and a temperature sensor on the other two wires. Agree with jraef's earlier post.

RE: I'm seeking advice on some 240v mot

Three clues from the nameplate:

"3~ motor" is a giveaway for a three phase motor as noted by Jeff and Scotty.

The two entries for 50 and 60 Hz supply frequencies suggest it's not specifically designed for inverter drive

The "Protector type PTO" bit at the bottom of the label corroborates their suggestion that the yellow leads are for thermistors embedded in the winding.


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