Motor And Converter Protection By Limiting The Voltage - Siemens SINAMICS G115D Operating Instructions Manual

Parameter
p0610[0...n]
p0625[0...n]
r0632[0...n]
p0640[0...n]
7.26

Motor and converter protection by limiting the voltage

What causes an excessively high voltage?
To drive the load, an electric motor converts electrical energy into mechanical energy. If the
motor is driven by its load, e.g. due to the load moment of inertia when braking, then the
energy flow reverses: The motor temporarily operates as generator, and converts mechanical
energy into electrical energy. The electrical energy flows from the motor to the converter. If
the converter cannot output the electrical energy supplied by the motor, e.g. to a braking
resistor, then the converter stores the energy in its DC link capacitance. As a consequence,
the DC link voltage Vdc in the converter is higher.
An excessively high DC link voltage damages the converter and also the motor. As a
consequence, the converter monitors its DC link voltage - and when necessary switches
off the motor and outputs fault "DC link overvoltage".
SINAMICS G115D Wall Mounted distributed drive
Operating Instructions, 07/2023, FW V4.7 SP14, A5E52808211A AA
7.26 Motor and converter protection by limiting the voltage
Description
Motor overtemperature response
Motor ambient temperature dur‐
ing commissioning [°C]
Mot_temp_mod stator winding
temperature [°C]
Current limit [A]
Advanced commissioning
Setting
Sets the system response when the motor temper‐
ature reaches the alarm threshold.
0: A07012, not reducing the current limit.
1: A07012 and F07011, reducing the current limit.
2: A07012 and F07011, not reducing the current
limit.
12: A07012 and F07011, not reducing the current
limit. (factory setting)
Note: After setting p0610 = 12 and switching off
the supply voltage, the converter saves the most
recently calculated 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.
Defines the ambient temperature of the motor for
calculating the motor temperature model.
Factory setting: 20
Displays the stator winding temperature of the mo‐
tor temperature model.
Sets the current limit.
Factory setting: 0
325