Not sure if this is the right place to post a feature request like this but here we go;
I plan to use the VESC6 in an industrial automation application (fancy name for a servo motor) and utilize its safety motor temperature protection feature, however during the build of a couple of prototypes I ran into the following problem:
We source motors with embedded NTC sensors placed(glued) right onto the winding end (we can't chose a different one). The Beta factor of the NTC in the motor is significantly different to the one that is hard coded in the firmware:
#define NTC_RES_MOTOR(adc_val) (10000.0 / ((4095.0 / (float)adc_val) - 1.0)) // Motor temp sensor on low side
#define NTC_TEMP_MOTOR() (1.0 / ((logf(NTC_RES_MOTOR(ADC_Value[ADC_IND_TEMP_MOTOR]) / 10000.0) / 3434.0) + (1.0 / 298.15)) - 273.15)
In some situations the motor becomes quite hot (whilst still in the specified operating region being max 100 degree C), when for example the real motor temp in a situation is 80 degrees C the VESC will read > 120C. Because of the difference in the real Beta factor with respect to the hard coded beta factor the temperature of the motor read by the VESC is different to the real temperature. The wrongly measured temperature in combination with the build in limit of the VESC-Tool is 120C (motor_start and motor_end temperature) makes it hard for me to utilize this awesome safety feature. We would like to use the motor to the max of 100C but we are currently limited to 80C.
I post this as a feature request because having the Beta factor of the external NTC configurable would benefit many other users with NTC with different Beta factors as well.
Possible simple workaround:
Change the VESC-tool configurable temperature range to an extreme like 200C. Whilst the temperature read by the VESC is still wrong, we are now able to implement the safety current throttling feature.
Make a new HW version define:
Changing the beta factor in the HW define solves the issue for individuals. The drawback is of course that a different HW release will have to be build for every different NTC Beta factor.
Having the NTC beta factor of the motor NTC configurable in the VESC-tool. This would be an ideal solution but does require some work on both the firmware and pc side software.
Thanks in advance for your time and consideration!