Risk of fire caused by the "sacrificing behav‐
ior" of the ZKS stage!
NOTICE
The "ZKS" input activates the "DC bus short circuit" function, when the 24V
control voltage has not been applied and when there isn't any current flowing
to the input. This condition can occur in the following situations:
●
Failure of 24V control voltage
●
Wire break
●
Activation of serially connected contacts (e.g. axis limit switches)
If the kinetic energy of the mechanical axis system regenerated when braking
is greater than the energy absorption capacity of HLB, the HLB device re‐
mains active when braking via ZKS takes place, until it is thermally destroyed
(sacrificing behavior). Risk of fire! In this case, braking via ZKS may only
come into effect in the case of an emergency (e.g. activation of an axis limit
switch causes the mains supply to be cut off and simultaneously causes the
24V supply of the ZKS input to be interrupted).
Install a 24V UPS, if the "sacrificing behavior" of HLB is relevant to your drive
system in the case of an emergency. This prevents the braking via ZKS
which causes HLB to be destroyed due to the failure of the 24V control volt‐
age. Braking via ZKS then will only take place in cases of emergency.
Type of motor and DC bus short circuit
Asynchronous drives do not decelerate when the DC bus voltage
has been short-circuited!
When the DC bus has been short-circuited, motors with perma‐
nent magnet excitation generate braking torque and are deceler‐
ated.
Bosch Rexroth AG
DOK-INDRV*-SYSTEM*****-PR06-EN-P
Rexroth IndraDrive Drive Systems with HMV01/02 HMS01/02, HMD01, HCS02/03
156/309
Circuits for the Mains Connection
