Siemens SINAMICS S120 - Motor Temperature Sensing

Monitoring functions and protective functions
9.5 Thermal motor protection
Drive functions
646 Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Thermal motor model 3
•
p0612[0...n]
Mot_temp_mod activation
•
p0613[0...n]
Mot_temp_mod 1/3 ambient temperature
•
r0631[0...n]
Mot_temp_mod stator iron tempe
rature
•
r0632[0...n]
Mot_temp_mod stator winding temperature
•
r0633[0...n]
Mot_temp_mod rotor temperature
•
p5350[0...n]
Mot_temp_mod 1/3 zero speed boost factor
•
p5390[0...n]
Mot_temp_mod 1/3 alarm threshold
•
p5391[0...n]
Mot_temp_mod 1/3 fault threshold
9.5.2
Motor temperature sensing
Temperature sensors
The motor temperature is sensed using temperature sensors integrated in the motor
windings. The sensors used are selected as standard from the following four different sensor
types:
● PTC
● KTY84
● PT100/PT1000
● Bimetallic sensor with NC contact (abbreviated, "bimetal NC contact")
Function of the PTC
The temperature sensor is connected to the Sensor Module at the appropriate terminals (-
Temp) and (+Temp) (see the relevant section in the SINAMICS S120 Control Units and
Supplementary System Components Manual). The threshold value for switching over to an
alarm or fault is 1650 Ω.
A PTC usually has a strongly non-linear characteristic, and as a consequence is used just
like a switch. When the typical rated response temperature is exceeded, then the resistance
changes abruptly (step function). The tripping resistance is ≥1650 Ohm.
● p0600 = 1 activates the motor temperature sensing using sensor 1
● p0601 = 1 sets temperature sensor type "PTC"