Braking Resistor (Armature Short-Circuit Braking); Description Of Function Braking Resistor - Siemens SIMOTICS 1FT2104-4AF Configuration Manual

Configuration

5.4 Braking resistor (armature short-circuit braking)

5.4 Braking resistor (armature short-circuit braking)
5.4.1

Description of function braking resistor

The motor cannot be electrically braked if, for converters
• The permissible DC link voltage values are exceeded
• The electronics fails
Then, the motor that is coasting down can only be braked using an armature short circuit.
You can switch the armature short-circuit braking internally via the Motor Module or
externally using a contactor circuit with braking resistors.
Armature short-circuit braking must be initiated at the latest by the limit switch in the
traversing range of the feed axis.
NOTICE
Damage to the drive at the end of the traversing range
To avoid mechanical damage, mount mechanical stops at the end of the absolute traversing
range.
NOTICE
Destruction of the converter as the armature short-circuit contactor incorrectly
switches
Incorrect switching of the armature short-circuiting contactor can erode the contactor
contacts and destroy the converter.
• Program the converter so that pulses are first canceled and this is actually implemented
In servo motors with an integrated holding brake, you can produce additional braking torque
with the holding brake.
Note
The holding brake is not a working brake to brake a spinning motor. A limited number of
EMERGENCY STOP operations is permissible.
Additional information is provided in Chapter " Brake (Page 50)".
Note
Braking under normal operating conditions must always be performed via the setpoint input.
For further information, see the configuration manual of the converter.
66
before an armature short-circuit contactor is closed or opened.
1FT2 synchronous motors for SINAMICS S120
Configuration Manual, 03/2021, A5E50645584B AA