Dc Link Components; Blocksize; Braking Resistors; Description - Siemens SINAMICS S120 Manual

DC link components

5.1

Blocksize

5.1.1

Braking resistors

5.1.1.1

Description

The PM240-2 Power Modules cannot feed back regenerated energy into the line supply. For
regenerative operation, e.g. the braking of a rotating mass, a braking resistor must be
connected to convert the resulting energy into heat.
A thermostatic switch monitors the braking resistor for overtemperature and issues a signal
on an isolated contact if the limit value is exceeded.
5.1.1.2

Safety instructions for blocksize braking resistors

Danger to life if the fundamental safety instructions and residual risks are not heeded
Failure to heed the fundamental safety instructions and residual risks in Chapter 1 can
result in accidents causing severe injuries or death.
• Follow the fundamental safety instructions.
• Consider the residual risks on the risk assessment.
Risk of fire and device damage as a result of ground fault / short-circuit
The cables to the braking resistor must be routed so that a ground fault or short circuit can
be ruled out. A ground fault can result in fire with associated smoke.
• Comply with local installation regulations, which allow this fault to be ruled out.
• Protect the cables from mechanical damage.
• In addition, apply one of the following measures:
AC Drive
Manual, (GH6), 07/2016, 6SL3097-4AL00-0BP5
WARNING
WARNING
– Using cables with double insulation.
– Observe adequate clearances, e.g. through the use of spacers.
– Route the cables in separate cable ducts or pipes.
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