Switching Energy / Operating Frequency - Wittur WSG-T0.1 Instructions De Service

Technical specifications
Disengagement time
The disengagement time is not influenced by DC or AC switching operations.
Engagement time
The transition from brake-torque free state to holding braking torque is not free of time lags.
For emergency braking, short engagement times for the brake are absolutely essential. The DC switching in
connection with a suitable spark suppressor is therefore to be provided.
❚ The engagement times apply for DC switching with a spark suppressor.
- Spark suppressors are available for the rated voltages.
If the drive system is operated with a frequency inverter so that the brake will not be de-energised before the
motor is at standstill, AC switching is also possible (not applicable to emergency braking). In this case, the
engagement times increase approximately by a factor of 5 (for connection refer to
3.4

Switching energy / operating frequency

1000000
100000
10000
1000
Abb. 3 Switching energy as a function of the operating frequency
S
The permissible operating frequency S
set operating frequency S
With high speeds of rotation and switching energy, the wear increases strongly, because very high temper-
atures occur at the friction surfaces for a short time.
INTORQ | BA 14.0197 | 04/2016
J
20S + 20S.1
22S
19S
18S + 18S.2
17S
100
1 10
Operating frequency S
Schalthäufigkeit S
S
–
hue
= ------------------------------ -
hmax
Q
 
R
ln 1 ------- -
–
 
Q
E
, the permissible amount of heat is Q
h
25S + 25S.1
28S
100
h
h
Q
S
max
depends on the amount of heat Q
hmax
31).
28S
-1
h
1000
– S
 
hue
---------------- -
S
 
h
= Q 1 e
–
 
E
 
(refer to Figure 3). At a pre-
R
.
Smax
19