Device functions
7.3 Coasting methods
3RW44 soft starters
Manual, 03/2017, NEB535219502000/RS-AB/008
133
DC braking torque
The motor's brake force can be set with the amount of the DC braking torque.
Coast-down time
The coast-down time specifies the period during which the DC braking torque is to be
generated on the motor. The chosen braking time should be long enough to bring the load to
a standstill.
To achieve an adequate braking effect down to standstill, the load's moment of inertia should
not exceed a maximum of 5 times that of the motor. (J
load
≤
5 x J
motor
).
Standstill detection does not take place in the soft starter and, if required, must be realized
by means of external measures.
Figure 7-9
DC braking
Typical applications for DC braking
Use "DC braking" in lathes (e.g. for tool change) or circular saws.