Lenze SDSGS - Manual (Page 26)

Mechanical installation
Holding brake (option)
Permanent magnet holding brakes
5
l
26 BA 13.0011−EN 1.0
5.4.2 Permanent magnet holding brakes
These brakes are used as holding brakes and serve to hold the axes without backlash at
standstill or in the deenergised state.
When activating the brake, it must be ensured that the brake is released or engaged at zero
speed to avoid unnecessary and rapid wear of the brake.
When used solely as holding brakes, the brakes are virtually wear free on their friction
surfaces. If the max. permissible switching energy per emergency stop (see catalogue) is
not exceeded, at least 2000 emergency stop functions from a speed of 3000 rpm are
possible.
W
+ ½ @ J
ges
@ w 2
W [J] Energy
J
tot
[kgm 2 ] Total moment of inertia
w [ 1 /
s
] Angular velocity w=2p n /
60
, n= speed [rpm]
The holding torques specified in the catalogue only apply when the motor is at standstill.
In the case of a slipping brake, the dynamic braking torque always applies which depends
on the speed.
(
Stop!
The holding brake is only designed for a limited number of emergency stops.
Utilisation as a working brake, e.g. to decelerate a load, is not permissible.
)
Note!
The brakes are maintenance−free and cannot be adjusted. In the event of wear,
e.g. through emergency stops, the brakes must be replaced.
These brakes operate according to the closed−circuit principle, i.e. the brake is closed in the
deenergised state.
Brakes with a rated voltage of DC 24 V are designed for smoothed DC voltages with a ripple
of <1 %. It must be ensured that the connector on the motor side is supplied with the
minimum voltage of DC 24 V −10 %. If necessary, the voltage drop in the cable should also
be considered. If the maximum voltage DC 24 V + 5 % is exceeded, the brake can close
again. Supplying the brake with bridge−rectified DC voltage (bridge rectifier without
additional smoothing) or a DC voltage with a ripple of >1 % can lead to a malfunctioning
of the brake or an increase in the engagement and disengagement times.
Brakes with a rated voltage of DC 205 V are designed for bridge−rectified DC voltage, i.e. for
supply via a bridge rectifier from the 230 V mains (half−wave rectifiers are not permissible).
Supplying the brake with smoothed DC voltage can lead to malfunctioning or an increase
in the engagement and disengagement times. With regard to the minimum and
maximum voltages, the same conditions apply as for brakes with 24 V, i.e. the permissible
voltage tolerance is 205 V DC +5 %, −10 %.