User Manual

Protection of the drive and the driven load
The protection functions prevent damage to the motor, inverter and driven load.
Overcurrent protection (Page 328)
Inverter protection using temperature monitoring (Page 329)
Motor protection with temperature sensor (Page 332)
Motor protection by calculating the temperature (Page 335)
Motor and inverter protection by limiting the voltage (Page 338)
The monitoring of the driven load prevents impermissible operating modes, e.g. dry-running
of a pump.
Monitoring the driven load (Page 340)
Increasing the drive availability
The kinetic buffering converts the kinetic energy of the load into electrical energy to buffer short-
term power failures.
Flying restart – switching on while the motor is running (Page 347)
The "Flying restart" function permits the fault-free switching on of the motor while it is still
turning.
Automatic restart (Page 349)
For active automatic restart, after a power failure, the inverter attempts to automatically restart
the motor and to acknowledge any faults that occur.
Kinetic buffering (Vdc min control) (Page 353)
In an emergency, the inverter deactivates its protection functions in order to maintain drive
operation as long as possible.
Essential service mode (Page 355)
Energy saving
For standard induction motors, the efficiency optimization reduces the motor losses in the
partial load range.
Efficiency optimization (Page 359)
The "Bypass" function switches the motor between inverter and line operation.
Bypass (Page 362)
If the plant/system conditions permit, the inverter switches off the motor temporarily.
Hibernation mode (Page 368)
If necessary, the main contactor control disconnects the inverter from the power system and
so reduces the inverter losses.
Line contactor control (Page 373)
The inverter calculates how much energy controlled inverter operation saves when compared
to mechanical flow control (e.g. throttle).
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Advanced commissioning
6.1 Overview of the inverter functions
Converter with the CU230P-2 Control Units
Operating Instructions, 04/2018, FW V4.7 SP10, A5E34257946B AF 197