12 Functional Descriptions 10.94
12.19.5 DC link buffering and monitoring of generator minimum speed limit
12.20.5 DC link buffering and monitoring of generator minimumspeed limit12.20.5.1 DC link buffering
An axis/spindle can buffer the DC link by means of generator-mode braking. This function can
be selected through appropriate parameterization of 611D machine data and activation of
generator operation by programming commands.
Generator operation
Drive MD 1634
600V/625V
ZK2 message:
DC link generator active
t
DC link voltage
Drive MD 1633
n_GEN
Drive MD 1632
Drive MD 1635
280V
Drive MD 1631
ZK2 message:
Generator speed < drive MD 1635
ZK2 message:
DC link voltage > drive
MD 1634
t
Actual speed value
When the DC link voltage drops below the minimum threshold value set in drive MD 1631, the
axis/spindle concerned switches from position-controlled or speed-controlled operation into an
operating mode controlled by the DC link. When the drive is braked (through input of speed
12–218
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SINUMERIK 840C (IA)