Siemens TV Converter Box 611 User Manual

 

System integration 

 

7.4 Braking concepts 

 

 

 

Note 
If armature short-circuiting braking is used without braking resistors, special contactors 

are required because the currents can be very high. - The release timing for the drive 

system must be taken into account. 

 

3.  Mechanical braking via braking elements: 

The braking capacity must be dimensioned as highly as possible so that the rotating 

masses can be reliably braked at maximum kinetic energy. 

Drawback:

 Depending on the speed, the relatively long response time of the brake 

controller may mean that the rotating mass continues to rotate for a while without being 

braked. 

We recommend that all three measures be implemented together. Measures (2) and (3) are 

used as an additional protection here in case measure (1) fails: The short-circuiting of the 

stator works at high speeds to begin with and then the mechanical brake takes effect at 

lower speeds. 
A list of recommended braking element manufacturers is provided in the appendix. 
 

Deploying a holding brake 

Due to cogging torques, torque motors can be pulled into a preferable magnetic operating 

position if the motor is no longer supplied with power from the drive. If the drive is already at 

a standstill, this can cause unexpected movements in up to a half magnetic pole pitch in both 

directions. To prevent any damage to the workpiece and/or tool, it may be advisable to use a 

holding brake. 
Due to the lack of a mechanical self-locking system, a holding brake should be installed for 

inclined or horizontal drives without weight compensation so that the drive can be shut down 

and de-energized in any position. 

 

WARNING 

 

For inclined and horizontal axes, the load may be reduced in an uncontrolled manner if the 

center of gravity is outside the rotary axes when the system is disconnected from the power 

supply. 

 

 
A holding brake may also be required if: 
●  The bearing friction does not compensate or exceed the cogging torques and unexpected 

movements result. 

●  Unexpected movements of the drive can lead to damage (e.g. a motor with a large mass 

also generates strong kinetic energy). 

●  Weight-loaded drives must be shut down and de-energized in any position. 

1FW6 Built-in torque motors 
Configuration Manual, 05/2009, 6SN1197-0AD00-0BP7 

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