Protecting the motor and inverter against overvoltage
The Vdc_max control avoids an excessively high DC link voltage, assuming that the
application permits this. The Vdc_max control increases the ramp-down time of the motor
when braking, so that the motor feeds back only as little energy to the inverter as is covered
by the losses in the inverter.
The Vdc_max control is not suitable for applications where the motor is continuously in the
generator mode. This includes, for example, cranes or applications involving braking large
moments of inertia. Further information on inverter braking methods can be found in Section
Braking functions of the inverter (Page 217).
Table 8- 17
p1280 = 1
For more information about this function, see the List Manual (function diagrams 6320 and
Information about the inverter state (alarms, faults, actual values) can be output via inputs
and outputs and also via the communication interface.
Details on evaluating the inverter state via inputs and outputs are provided in Section Adapt
inputs and outputs (Page 117).
The evaluation of the inverter state via the communication interface is realized using the
inverter status word. Details on this are provided in the individual sections of Chapter
Configure fieldbus (Page 125).
SINAMICS G110M Operating Instructions
Operating Instructions, 04/2015, FW V4.7.3, A5E31298649B AD
p1240 = 1
1)1: Enable V
Shows the value of the DC-link voltage above which the V
controller is active
of the control parameters P1290, P1291 and P1292
setting p1294: 0, factory setting p1254: 1)Activates or deac-
tivates automatic detection of the switch-on levels of the V
0: Automatic detection disabled
1: Automatic detection enabled
Unit supply voltage
If p1254 or p1294 = 0, the inverter uses this parameter to calcu-
late the intervention thresholds of the V
Set this parameter to the actual value of the input voltage.
controller or V
monitoring configuration(factory setting:
controller switch-on level
controller dynamic factor (factory setting: 100 %) scaling
controller automatic recording ON-signal level(factory
8.8 Status messages