Siemens Sinamics G120P Operating Instructions Manual page 336

Functions
7.2 Inverter control
Inverter states and commands for switching the motor on and off
In addition to the OFF1 command, there are other commands that are used to switch off the
motor:
● OFF2 - the inverter is immediately switched off electrically, the motor coasts down.
● OFF3 - this command means "quick stop". After OFF3, the inverter brakes the motor with
the OFF3 ramp-down time. After reaching standstill, the inverter switches off the motor.
The command is frequently used for exceptional operating situations where it is
necessary to brake the motor especially quickly.
Figure 7-1
The abbreviations S1 ... S5b to identify the inverter states are defined in the PROFIdrive
profile.
Inverter status
S1
S2
S3
S4
S5a
S5b
336
Internal sequence control of the inverter when the motor is switched on and off
Explanation
In this state, the inverter does not respond to the ON command. The inverter goes
into this state under the following conditions:
ON was active when switching the inverter on.
•
Exception: When the automatic restart function is active, ON must be active after
switching the power supply on.
OFF2 or OFF3 is selected.
•
This state is required to switch on the motor.
The inverter waits for the operating enable.
If the inverter is controlled via a fieldbus, then you must set the operating enable in a
control word bit.
If the inverter is exclusively controlled via its digital inputs, then the operating enable
signal is automatically set in the factory setting.
The motor is switched on.
The motor was switched off with OFF1 and brakes with the ramp-down time of the
ramp-function generator.
The motor was switched off with OFF3 and brakes with the OFF3 ramp-down time.
Inverter cabinet units
Operating Instructions, 12/2014, A5E32923362A