7.3
Braking Resistor
Braking resistor
The braking resistor is designed for the SINAMICS G120 inverters with an internal brake
chopper and 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 inverter. This causes the
voltage to rise in the DC link. The inverter transfers the excess energy to the externally
mounted braking resistor.
7.3.1
Mounting the braking resistors
The following points must be taken into account generally:
● Sufficient space must be available for dissipating the energy converted by the braking
● A sufficient distance from flammable objects must be maintained.
● The braking resistor should not be installed underneath fire detection systems, since
● For outdoor installation, a hood should be provided to protect the braking resistor against
Power Module PM240
Hardware Installation Manual, 07/2009, A5E00807525B AD
resistor.
these could be triggered by the resulting heat.
precipitation (in accordance with degree of protection IP20).
Accessories
7.3 Braking Resistor
107