Gearless Lift Machine
WSG-18 and WLG-18
Operating Instructions
Seite/page
14
Datum/date
14.02.2006
Stand/version
0.17
Änderungen vorbehalten!
Subject to changes without notice!
MADE BY
SAD GmbH
A MEMBER OF WITTUR
7.4. Brake
The brakes are supplied with d.c. voltage by the overexci-
tation rectifier, which is supplied separately. The rectifier
should be installed in the control cabinet of the lift sys-
tem. It can be snapped on a mounting rail as specified in
EN 50 022.
The overexcitation period and the holding voltage can be
adjusted separately. They are factory-set by the manufac-
turer and must not be changed (see section – Technical
data).
To reduce the switch-off time, switching
can be effected from the d.c. side. Howev-
er, it is also required to provide switching
from the a.c. side at the same time)!
The overexcitation rectifier is supplied as
standard with a bridge installed between
contacts A8 and A9, meaning that a.c. side
switching is preset.
Note on the use of d.c./a.c. side switching:
A.c. side switching is recommended for nor-
mal operation, since the lift machine is
then decelerated in a controlled manner to
zero speed and the switching noise of the
brake is negligible.
When braking in the event of a breakdown
(emergency stop) or during an inspection
drive, the switching should be performed
from the d.c. side, since this ensures a
faster braking effect with the car being
stopped earlier.
Monitoring the brakes
The switching state and wear of the brakes are monitored
by means of dust-proof microswitches with gold con-
tacts. The contacts are designed as n.c. contacts, i.e. the
contact is opened if the armature is attracted (brake
released). It is possible to change the micro switch con-
tacts into n.o. contacts, if required.
Max. current carrying capacity of the monitoring
contacts:
250 V AC / 3 A (resistive load)
Note
Note
T
L
time for releasing the brake
T
S~
switching-off time - A.c. side switching
T
S=
switching-off tim - D.c. side switching
Note
: The above swiching times are guide values under
reference conditions.
A.c. side switching
•
Low-noise switching of the brake
•
No protective measures required for switching contact
•
Slow application of the brake.
~
+
-
Br
D.c. side switching
•
Noisy switching
•
Burn-up protection for switching contact required
(e.g. varistor, free-wheeling diode)
•
Fast application of the brake.
-
+
Br
~
Monitoring
Brake
dropped
released
Releasing
NC
NO
Wear
Brake lining new
NC
NC
Brake lining worn
NO
NC
Switching state s of brake monitoring contacts
T
L
/ ms
T
S~
/ ms
T
S=
/ ms
WSG-18.1
~ 180
~ 610
~ 75
WSG-18.2
~ 230
~ 260
~ 45
WSG-18.3
~ 320
~ 250
~ 40
WLG-18.A
~ 160
~ 800
~ 90
WLG-18.B
~ 190
~ 520
~ 75
WLG-18.C
~ 230
~ 260
~ 45
Switching times WxG-18 with twin shoe brake
