Thermistor Protection - Siemens SIMOCODE pro Operating Manual

Parameters
4.1 Motor protection
4.1.5

Thermistor protection

Description
Thermistor protection is based on a direct temperature measurement in the motor via binary
PTC thermistors which can be connected to the SIMOCODE pro basic unit.
Thermistor protection is used in the case of:
● Motors with high switching frequencies
● Converter operation
● Motors with heavy starting
● Intermittent duty and/or braking operation
● Restricted air supply
● Speeds below the rated speed.
In this case, the sensors are mounted in the winding slot or bearing of the motor.
Schematic and characteristic curve
The resistance of the thermistors increases rapidly (abruptly) when the temperature limit is
reached.
Figure 4-7
50
Thermistor function block (thermistor protection)
SIMOCODE pro - Parameterize
Operating Manual, 04/2017, A5E40507630002A/RS-AA/001