Motor Protection By Calculating The Temperature - Siemens SINAMICS G120D Operating Instructions Manual

Advanced commissioning

8.21 Motor protection by calculating the temperature

8.21 Motor protection by calculating the temperature
Overview
The converter calculates the motor temperature based on a thermal motor model. After
commissioning, the converter sets the thermal motor type to match the motor.
The thermal motor model responds far faster to temperature increases than a temperature
sensor.
If the thermal motor model is used together with a temperature sensor, e.g. a Pt1000, then the
converter corrects the model according to the measured temperature.
Function description
Thermal motor model 2 for induction motors
The thermal motor model 2 for induction motors is a thermal 3-mass model, consisting of stator
core, stator winding and rotor. Thermal motor model 2 calculates the temperatures - both in the
rotor as well as in the stator winding.
Figure 8-59
Parameter
Table 8-54
Number
r0034
r0068[0 ... 1]
p0344[M]
p0604[M]
p0605[M]
p0610[M]
p0612[M]
p0625[M]
p0627[M]
r0632[M]
p0640[D]
264
Thermal motor model 2 for induction motors
Thermal motor model 2 for induction motors
Name
CO: Thermal motor load
CO: Absolute actual current value
Motor weight (for thermal motor model)
Mot_temp_mod 2/KTY alarm threshold
Mot_temp_mod 1/2/sensor threshold and temperature value 145 °C
Motor overtemperature response
Mot_temp_mod activation
Motor ambient temperature during commissioning
Motor overtemperature, stator winding
Mot_temp_mod stator winding temperature
Current limit
Converter with the control units CU240D-2
Operating Instructions, 10/2020, FW V4.7 SP13, A5E34262100B AH
Factory setting
- %
- Arms
0 kg
130 °C
12
0000 0010 0000
0010 bin
20 °C
80 K
- °C
0 Arms