Gearless Lift Machine
WSG/WGG-29
Operating Instructions
Code
GM.8.002662.EN
Date
04.02.2019
Version
0.19
Page
13
Subject to changes without notice ! Subject to changes without notice !
EN
4.2.4. Brake
• Please refer also to the operating instructions for the brake.
• The brakes are supplied with DC voltage by the overexcitation rectifiers, which are fitted in the brake
terminal box.
• Only the overexcitation rectifiers which are included in our scope of supply are to be used for the brake acti-
vation.
• Repeated switching of the brake magnets during the overexcitation period must be avoided as this will result
in overloading of the brake control unit. Therefore, a minimum brake operating time of approx. 1.5 – 2 s
should be maintained, especially during an inspection or commissioning drive.
• To reduce the switch-off time, switching can be effected from the DC side. However, switching must also be
performed from the AC side at the same time ! (Wiring with a varistor as shown in the circuitry suggestion
on page 15!)
Note on the use of DC/AC side switching:
AC side switching is recommended for normal operation, since the lift machine is then decelerated in a con-
trolled 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 DC side, since this ensures a faster braking effect with the car being stopped
earlier. We therefore recommend the use of 2 separate contactors for the brake control circuitry, one of
which switches at the DC side, the other at the AC side.
AC side switching
• Low-noise switching of the brake
• No protective measures required for switching
con tact
• Slow application of the brake.
DC side switching
• Noisy switching
• Burn-up protection for switching contact required
(e.g. varistor, free-wheeling diode)
• Fast application of the brake.
~
+
-
Br
-
+
Br
~
Attention:
schematic diagram!
Attention:
schematic diagram!
