Siemens SINAMICS G120D Operating Instructions Manual page 267

Thermal motor model 3 for encoderless synchronous motors
The thermal motor model 3 for encoderless synchronous motors 1FK7 or 1FG1 is a thermal 3-
mass model, consisting of stator core, stator winding and rotor. Thermal motor model 3
calculates the temperatures - both in the rotor as well as in the stator winding.
Figure 8-60
Table 8-55
Parame‐
ter
r0034
r0063
r0068
p0610
p0612
p5390
p5391
Converter with the control units CU240D-2
Operating Instructions, 10/2020, FW V4.7 SP13, A5E34262100B AH
Thermal motor model 3 for 1FK7 encoderless synchronous motors
Thermal motor model 3 for 1FK7 encoderless synchronous motors
Description
CO: Thermal motor load [%]
CO: Actual speed value [rpm]
CO: Actual current value [A]
Motor overtemperature response (factory setting: 12)
0: Alarm A07012
The converter does not reduce the current limit.
1: Alarm A07012 and fault F07011
The converter does not reduce the current limit.
2: Alarm A07012 and fault F07011
The converter does not reduce the current limit.
12: Alarm A07012 and fault F07011
The converter does not reduce the current limit.
After switching off the supply voltage, the converter saves the most-recently calcu‐
lated difference to the ambient air temperature. After switching the supply voltage on
again, the thermal motor model starts with 90 % of the previously saved difference
temperature.
Mot_temp_mod activation
.02 1 signal: Activate motor temperature model 3 for
1FK7 or 1FG1 encoderless synchronous motors
Mot_temp_mod 1/3 alarm threshold (factory setting:
110.0° C)
Motor temperature > p5390 ⇒ alarm A07012.
Mot_temp_mod 1/3 fault threshold (factory setting:
120.0° C)
Motor temperature > p5391
or
motor temperature > p5390, longer than a motor-depend‐
ent time calculated by the converter
⇒ fault F07011.
8.21 Motor protection by calculating the temperature
Advanced commissioning
After selecting an encoderless
synchronous motor 1FK7 or
1FG1 (p0300) or a listed induc‐
tion motor (p0301) during the
commissioning, the converter
sets thermal motor model 3
and the parameters to values
appropriate for the motor type.
The parameters are write-pro‐
tected for listed motors
(p0301 ≥ 0).
265