Technical data

MKE UL/CSA Notes Regarding Application 12-5
DOK-MOTOR*-MKE*UL/CSA*-PR01-EN-P
12.4 Holding brake
Optional. Holds the servo axis when no power is being supplied to the
machine.
DANGER
Falling axes! Danger to personnel. Extremities
could be pinched or severed.
Þ The holding brake itself does not guarantee personnel
safety!
Þ Ensure the personnel protection by using additional
protective measures
Þ block off the hazardous area using protective bars or
gratings.
Þ in addition, secure vertical axes against falling or
lowering after the motor is switched off by, for
example:
- mechanically locking the vertical axis
- attaching an external braking/catching/clamping
device, or
- sufficiently balancing the weight of the axis
The holding brake works according to the “electrically releasing” principle.
When not under power, a magnetic force acts on the brake armature disk.
As a result, the brake closes and holds the axis.
When 24 V
DC is applied, the continuous magnetic field is compensated
for by the electrically generated magnetic field: the brake opens.
t
U
n
[V]
0
24
t
1
t
2
brake_diagr.fh7
t
1
: Clamp time
t
2
: Release time
Fig. 12-7: Brake operation
The brake is controlled by the drive controller. This ensures the correct
sequence of switching on/off in all operating modes.
Note: Premature wear of the holding brake is possible!
The brake wears out after approx. 20,000 motor revolutions in
a closed state. Therefore, do not use the brake to stop a
moving axis during operation! This is permitted only for
EMERGENCY STOP (E-stop) situations.
Note the guidelines regarding commissioning the brake in the
“Commissioning, Operation and Maintenance” chapter.