Siemens SINAMICS S120 Manual page 51

The following diagrams show the dependencies of motor cable length, motor holding brake
current and cross-section of the motor holding brake cables:
Module input voltage 24 V
Note
Protective circuit against overvoltages
The Motor Modules have an integrated overvoltage protection circuit for the motor holding
brake. External protective circuits are not required.
Electric shock caused by high touch voltages for braking cables
For motor cables with integrated brake cable, when the motor is operated, the motor can
charge the brake cable up to hazardous voltage levels. Coming into contact with the
conductors or the shield of the brake cable can result in death or serious injury.
• Use motor cables with separate, shielded brake cables.
• Connect the shield of the brake cable at both ends.
NOTICE
Premature wear of the motor holding brake when incorrectly operated
Operating the motor holding brake outside its permissible voltage range at the motor
connection will damage the brake.
• Ensure that the motor holding brake is only operated within its permissible voltage
Power Units in Booksize C/D-Type Format
Manual, 12/2018, 6SL3097-5AC20-0BP0
WARNING
range.
Motor Modules in booksize C/D-type format
3.3 Interface description
Module input voltage 26 V
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