WITTUR WSG-TB.3 series, Руководство по эксплуатации

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Technical specifications
INTORQ | BA 14.0197 | 04/2016 19
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
31).
3.4 Switching energy / operating frequency
Abb. 3 Switching energy as a function of the operating frequency
The permissible operating frequency S
hmax
depends on the amount of heat Q
R
(refer to Figure 3). At a pre-
set operating frequency S
h
, the permissible amount of heat is Q
Smax
.
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.
100
1000
10000
100000
1000000
1 10 100 1000
Sc
ha
lta
rbe
it Q
R
J
Schalthäufigkeit S
h
28S
h
-1
20S + 20S.1 22S
18S + 18S.2
19S
17S
28S
25S + 25S.1
Switching energy Q
R
Operating frequency S
h
S
hmax
S
hue
–
ln 1
Q
R
Q
E
-------- –
 
 
------------------------------- =
QS
max
Q
E
1 e
S
hue
–
S
h
-----------------
–
 
 
 
 
=