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How do I fix an F16 Motor Thermal Protection code for a DG1 drive?

Motor over temperature is a calculated trip in the drive. There are quite a few factors that the drive takes into consideration when it is calculating this trip. The settings in the drive that affect this trip are: motor nameplate current, motor nameplate frequency, motor ambient temperature factor, motor zero frequency current, motor heating time constant and duty cycle. With the basic start up the 2 settings that are set during a start-up are the motor nameplate and motor nameplate frequency. The other settings in the drive are defaulted for normal NEMA1 drip proof motors. These parameters set up the heating curve of the drive. With these settings the drive will allow running at 100% current on the motor continuously at 100% speed. One thing to note is that the motor has a service factory of 1 when running with a VFD due to the high fre-quency heating of the VFD. Below is list of what each of the settings do to the curve: • Motor nameplate current: this sets the continuous current rating of the motor. • Motor nameplate frequency: on a motor that has a shaft driven fan this sets the frequency at which the motor can continuously run motor nameplate current. • Motor ambient temp: when the drive first starts up it uses its temp as the temp of the motor. When this setting is 0 it means the motor is at the same temp as the drive. If the motor is in a significantly different ambient temp than the drive this parameter would be used to correct for the temperature difference . An example of this would be if the motor is on a roof out in the desert with an ambient outside of 110F whereas the drive is in an air conditioned room at 70F this would suggest setting to about 15%. • Motor zero frequency current: This is the % of FLA that the motor can run at zero speed. If the motor is cooled by an external blower or water jacket this can be drastically changed and put close to 100%. The thing that normally limits this is the cooling on the motor. • Motor heating time constant: This is basically how long it takes the motor to heat up to 63% of 100% temp. Normally the bigger the motor the longer this time is. Unless this # from the motor manufacturer is provided it should not be change value. • Motor duty cycle: This is the duty cycle of the motor. This should be on the nameplate of the motor. Motor over temperature fault is normally an application fault although it is good to check all of the above values to make sure they are correct. Check the parameters that are captured when the drive faulted out. The main thing to look for is the frequency of the drive and the output current. The default motor curves is calculating this for a shaft driven fan so full current can only be run at full speed . What to look for is to much current for the speed that the drive is running at. The trip level is at 105%. In most cases the fault is due to simply drawing to much current for the speed that the drive is running at which is an application problem.