Load Torque Monitoring (System Protection) - Siemens SINAMICS G110D Operating Instructions Manual

Functions
6.8 Protection functions
6.8.5

Load torque monitoring (system protection)

Applications with load torque monitoring
In many applications, it is advisable to monitor the motor torque:
● Applications in which the mechanical connection between the motor and load may be
interrupted (e.g. if the drive belt in fan or conveyor belt systems tears).
● Applications that are to be protected against overload or locking (e.g. extruders or
mixers).
● Applications in which no-load operation of the motor represents a critical situation (e.g.
pumps).
Load torque monitoring functions
The inverter monitors the torque of the motor in different ways:
1. No-load monitoring:
The inverter generates a message if the motor torque is too low.
2. Lock protection:
The inverter generates a message if the motor speed cannot match the speed setpoint
despite maximum torque.
3. Stall protection:
The inverter generates a message if the inverter control has lost the orientation of the
motor.
4. Frequency-dependent torque monitoring:
The inverter measures the current torque and compares it with a parameterized
frequency/torque characteristic.
Table 6- 36
Parameter
No-load monitoring
P2179 = ...
P2180 = ...
Lock protection
P2177 = ...
Stall protection
P2178 = ...
128
Parameterizing the monitoring functions
Description
Current limit for no-load detection
If the inverter current is below this value, the message "no load" is output.
Delay time for the "no load" message
Delay time for the "motor locked" message
Delay time for the "motor stalled" message
Operating Instructions, 07/2016, FW V3.63, A5E36768472B AB
SINAMICS G110D