Temperature monitoring, terminals T1/T2 of the 9300, interferences

Why should the cables for the motor temperature monitoring should, in case of 9300, not be connected to the terminals T1/T2, when in the motor there is no thermal sensor (PTC sensor or temperature contact)?

If the cores of the motor system cable are connected, although there is no temperature sensor in the motor, these cores of high resistance have an antenna effect.

Consequently, high interference injections can disturb the drive controller with following possible consequences:
  • A high interference level could occur on the analog output signals terminal 62 + 63.
  • The drive could run out of round with 'humming' noises.
  • No position repeatability accuracy of the absolute positioning
  • Occurrence of CCr system interference
  • Reset of the parameters stored in a volatile mode in the RAM of the drive controller

Generally, these cores are supposed to be shielded and not to be connected, when there is no thermal sensor.

The malfunction information OH8 (motor temperature) is given, when no thermal sensor is connected and the function has not been inactivated with C0585 = 3.