Siemens SINAMICS S120, Function Manual

Page: 580 / 1094

Function modules
8.11 Extended stop and retract
Drive functions
580
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
8.11.4.3 Regenerative operation
In the case of a fault, the objective is to buffer the DC link until all of the drives connected to
the DC link and enabled by ESR have reached their configured final position. To achieve
this, a suitable drive in the drive line-up, for example a spindle drive, is braked in generator
operation. The DC-link voltage is then monitored by the V
dc_min
controller.
Configuring the "Generator operation" response
1. Set the generator operation of the drive with the parameter setting p0888 = 3.
2. Parameterize the V
dc
controller.
3. Activate the monitoring of the DC-link voltage for the generator operation with the
parameter setting p1240 = 2.
4. Set the permissible lower voltage limit V
dc_min
of the DC link via parameter p1248.
The infeed detects when the power fails as the DC-link voltage drops and this is then
signaled as an alarm.
Figure 8-31 DC-link voltage setpoint
8.11.5 Restrictions for ESR
● Operating several axes in the generator mode
Only use one speed-controlled axis to buffer the DC link. If you have parameterized
several axes, faults can occur, which undesirably influence one another and therefore the
drive line-up as a whole.
● Motors that are not suitable for generator operation
Linear motors (1FN) and torque motors (1FW) require an adequately high DC-link voltage
to brake. They are not suitable to buffer the DC link when operating in the generator
mode.
● ESR and Safety Integrated
If the Safety Integrated Extended Functions are controlled via PROFIsafe, in the case of
a communication failure, Safety Integrated only permits a response time (p9580/p9380)
of maximum 800 ms. After this time expires, Safety Integrated requests pulse
suppression.