Braking Resistor - Siemens SINAMICS G12 Hardware Installation Manual

9.6

Braking resistor

The braking resistor enables loads with a large moment of inertia to be braked quickly. During
braking of the motor and the load, excess energy is fed back to the converter. This causes the
voltage to rise in the DC link. The converter transfers the excess energy to the externally
mounted braking resistor.
Fire caused by an unsuitable or incorrectly installed braking resistor
Using an unsuitable or improperly installed braking resistor can cause fires and smoke to
develop. Fire and smoke development can cause severe personal injury or material damage.
● Only use braking resistors that are approved for the inverter.
● Install the braking resistor in accordance with regulations.
● Monitor the temperature of the braking resistor.
Mounting position
Mounting instructions
Mount the resistor on a heat resistant surface with a high thermal conductivity.
Do not cover the ventilation openings of the braking resistor.
You can mount the braking resistor either outside or inside the switchgear room. When
mounted outside, the cooling air requirement for the switchgear room is lower.
Clearances to other devices
The following data are applicable for devices, frame sizes FSA ... FSC.
The clearances for braking resistors for devices, frame sizes FSD ... FSF are specified in the
documentation, which is supplied with the braking resistor.
Power Module PM240-2
Hardware Installation Manual, 08/2017, A5E33294624B AG
WARNING
Accessories
9.6 Braking resistor
131