Bosch MSK030B-0900-NN, Project Planning Manual

Page: 223 / 282

9.10 Holding brakes
9.10.1 Holding brake electrically releasing
Holding brakes of MSK motors work according to the principle of "electrically
releasing". The holding brakes are released when applying the switching volt‐
age.
The power supply of the holding brake must be designed in such a way as to
guarantee under the worst installation and operation conditions that sufficient
voltage of 24 V ±10% is available on the motor in order to bleed the holding
brake.
t
U
N
[V]
0
24
MKE00106
t
2
t
1
t
1
Connection time
t
2
Disconnection time
Fig. 9-12: Switching condition holding brake over time
The holding brake is used to hold axes at standstill and with drive enable
switched off. If the supply voltage fails or the drive enable is switched off,
electrically releasing holding brakes close automatically.
Do not use the holding brake as a service brake for moving axes.
If the holding brake is repeatedly activated while the drive is rotating or the
permissible braking energy is exceeded, premature wear may occur.
9.10.2 Holding brakes safety instructions
Observe the safety requirements when designing the system.
Serious bodily injury due to dangerous move‐
ments caused by dropping or sinking axes!
WARNING
Secure vertical axes against dropping or sinking after switching off by e.g.:
●
Mechanical locking of the vertical axis
● External brake, arrestor, clamping device.
● Axis weight compensation
The holding brakes supplied as standard and controlled by the
controller alone are not suitable for personal protection!
Personal protection must be achieved by means of overriding fail-
safe measures, such as e.g. danger zones that are sealed off by
protective fences or protective grids.
DOK-MOTOR*-MSK********-PR12-EN-P Bosch Rexroth AG 221/279
Synchronous Servomotors MSK
Operating conditions and application notes