DOL motors & Thermistors
DOL motors & Thermistors
(OP)
I have a motor 4kW, DOL Start, with a Telemechanique GV2ME14 Motor Circuit Breaker.
The motor an ATEX rated Motor and is installed in ATEX Zone 2 area.
The motor manual is not clear on whether the Thermistor has to be wired if the motor is not fed from an inverter. I have emailed the manufacturer and am waiting for a response.
In a non hazardous area I would typically not use thermistor protection on a DOL Motor, but I would use a thermistor if the motor is fed by an VFD.
Similarly I would definitely use a Thermistor on a VFD fed motor in a Hazardous area.
However I am not sure if it is needed for a DOL fed motor. The fan should be more than capable of keeping the motor below the rated temperature, however if there was damage to the motor fan, or the intake was blocked it would be conceivable that the motor could heat up but the Motor protection would not trip.
The motor an ATEX rated Motor and is installed in ATEX Zone 2 area.
The motor manual is not clear on whether the Thermistor has to be wired if the motor is not fed from an inverter. I have emailed the manufacturer and am waiting for a response.
In a non hazardous area I would typically not use thermistor protection on a DOL Motor, but I would use a thermistor if the motor is fed by an VFD.
Similarly I would definitely use a Thermistor on a VFD fed motor in a Hazardous area.
However I am not sure if it is needed for a DOL fed motor. The fan should be more than capable of keeping the motor below the rated temperature, however if there was damage to the motor fan, or the intake was blocked it would be conceivable that the motor could heat up but the Motor protection would not trip.





RE: DOL motors & Thermistors
You may want to wire it and use the added protection for the motor.
RE: DOL motors & Thermistors
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RE: DOL motors & Thermistors
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