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I have a triple voltage motor with 12 leads. I know how dual voltage motors work by hooking the windings in series or parallel. Does anyone know how its done for three voltages, checked online but could not find a winding diagram?




Just noticed this is one of the motors that say to "use a manual momentary start switch only" this just came up the other day.
 

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The motor has six windings. For low voltage it is wired in a double delta, for medium voltage it is wired in a double wye, and for high voltage it is wired in a single delta. The windings would each be rated for 230 volts. With the low and high voltage connections each winding would see 230 volts. For the 380 volt connection each winding would see ~220 volts.

As far as the momentary start circuit, that is required because of the thermostat connections in the motor. Those connections are wired into the motor control circuit so that if the motor overheats the starter will drop out and the power will be removed from the motor. With a momentary start button, restarting the motor after a high temperature trip will require manual intervention. If the control system was a "maintained start" system, the motor would stop when it was too hot, but would automatically restart when the motor cools enough for the internal temperature switch to return to its normal state.
 

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As far as the momentary start circuit, that is required because of the thermostat connections in the motor. Those connections are wired into the motor control circuit so that if the motor overheats the starter will drop out and the power will be removed from the motor. With a momentary start button, restarting the motor after a high temperature trip will require manual intervention. If the control system was a "maintained start" system, the motor would stop when it was too hot, but would automatically restart when the motor cools enough for the internal temperature switch to return to its normal state.
First off, I'm not trying to argue with you. I am a student and just finished motor controls and I am curious. If you use a momentary start button, the motor starter would have to be latched for continuous run on the motor? If so, if the motor does overheat, will it trip the overloads on the motor starter?
 

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First off, I'm not trying to argue with you. I am a student and just finished motor controls and I am curious. If you use a momentary start button, the motor starter would have to be latched for continuous run on the motor? If so, if the motor does overheat, will it trip the overloads on the motor starter?
Yes indeed, the starter would need to have a latch in order to stay closed. And yes, if the O/Ls tripped, the starter would drop out and the momentary start button would have to be pushed in order to get it to run.

Typically, thermostats embedded in the motor windings (like the J wires in the OPs motor) are connected in series with the stop button. That way, if they open, it's the same as pushing the stop button.
 

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micromind said:
Yes indeed, the starter would need to have a latch in order to stay closed. And yes, if the O/Ls tripped, the starter would drop out and the momentary start button would have to be pushed in order to get it to run. Typically, thermostats embedded in the motor windings (like the J wires in the OPs motor) are connected in series with the stop button. That way, if they open, it's the same as pushing the stop button.
Cool, thanks. Just learned something else. That will help me look like I know something when my instructor starts going over motors, lol.
 
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