Wittur Servogearless WSG-S2.3 Instructions De Service page 54

Technical specifications
The division of the brake circuits is done using a two-part armature disk (2) with the respectively allocated
compression springs (1.2) and electromagnetic coils (8). Each brake circuit can be operated individually due
to the separate supply lines for each coil group and armature disk segment (
a microswitch (16) which monitors the switching state of the spring-applied brake. Using the associated
switching device, the supply voltage (AC voltage) is rectified and, when the brake is released, lowered after
a short period of time. This results in a reduction of the average electrical power of the brake.
The stator (1) is supplied in heat class F. The limit temperature of the coils (8) is 155 °C. The BFK464 spring-
applied brake is designed for a maximum operating time of 60 % with holding current reduction.
Certificate
Type
BFK464-17S
BFK464-18S
BFK464-18S.2
BFK464-19S
BFK464-20S
BFK464-20S.1
BFK464-22S
BFK464-25S
BFK464-25S.1
BFK464-28S
3.1.2 Braking
During the braking procedure, the pressure springs (1.2) use the armature plate (2) to press the rotor (3)
(which can be shifted axially on the hub (4)) against the friction surface. The asbestos-free friction linings
ensure high braking torque and low wear. The braking torque is transmitted between the hub (4) and the rotor
(3) via gear teeth.
3.1.3 Brake release
When the brakes are applied, an air gap "s
ment (1). To release the brake, the coils (8) of the existing magnetic circuit are supplied with the correct DC
voltage. The resulting magnetic force works against the spring force to draw the armature plate segments
(1) to the stator (7). This releases the rotor (3) from the spring force and allows it to rotate freely
3.1.4 Release monitoring
The spring-activated brake has a microswitch (16) for each braking circuit to monitor the switching state.
When the brake is released, the microswitches (16) toggle. This means that it is possible to exclude the drive
being operated when the brake is closed. The microswitches can be connected as both normally open and
also normally closed.
To check that the microswitches function correctly, we recommend testing the switching status (refer to table
6) in both the released and applied braking states.
INTORQ | BA 14.0197 | 04/2016
EC-type examination certificate
Directive 95/16/EC
ABV 948/1
ABV 862/1
ABV 903/1
ABV 863/1
ABV 849/1
ABV 850/1
ABV 975/1
ABV 851/1
ABV 869/1
ABV 859/1
" is present between the stator (1) and the armature plate seg-
L
32). Each brake circuit has
UCM Directive 2014/33 EU
ESV 948/1
ESV 862/1
ESV 903/1
ESV 863/1
ESV 849/1
ESV 850/1
ESV 975/1
ESV 851/1
ESV 869/1
ESV 859/1
EU-BD 948
EU-BD 862
EU-BD 862
EU-BD 863
EU-BD 849
EU-BD 849
EU-BD 975
EU-BD 851
EU-BD 851
EU-BD 859
14