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Siemens MD 50.1 · 2015
Motor options
Mounted components
11
■
Backstop
Motors, sizes 71 to 200, can be supplied with a backstop, which
prevents them from rotating in the opposite direction to that used
in operation.
Above the disengage speed, in the operational direction of rota-
tion, there is no connection between the inner and outer rings
of the backstop.
For starting and stopping below the disengage speed, the oper-
ating time may be a maximum of 20 seconds.
In the direction of rotation opposite to the operational direction of
rotation, there is a fixed connection between the inner and outer
rings of the backstop. This allows the rated backstop torque
to be transmitted.
When selecting the backstop, the direction of rotation of the
geared motor output shaft must be specified.
Please note that motor speeds that are lower (e.g. in inverter-fed
operation) than the disengage speed can damage the
backstop.
Fig. 11/44
Backstop
Technical specifications
Modular system in combination with backstop
Order code:
Backstop
1)
N23
1)
Not possible for worm geared motors S
Order code, output shaft direction of rotation:
Clockwise
K18
Counterclockwise
K19
2
3
4
1
G_D087_EN_00146
Cage
Motor end shield
Backstop flange
Backstop cover
2
3
4
1
Motor size
Rated torque
Disengage speed
Maximum speed
Weight
Moment of inertia of
cage and inner ring
T
SP
n
dis
n
max
m
Bstp
J
Bstp
Nm
min
-1
min
-1
kg
10
-4
kgm
2
71
100
890
5 000
0.26
1.0
80
100
890
5 000
0.26
1.0
90
150
860
5 000
0.42
2.0
100
150
860
5 000
0.42
2.0
112
150
860
5 000
0.42
2.0
132
420
750
5 000
1.16
8.0
160
800
700
5 000
1.16
8.0
180
1 050
670
5 000
1.60
20.0
200
1 050
670
5 000
1.60
20.0
225
1 350
630
5 000
4.20
27.0
250
1 350
630
5 000
4.20
27.0
Modular system
Motor plug
Brake
Encoder
Self ventilation
Forced ventilation
Second shaft
extension
Backstop
✓
-
✓
✓
✓
© Siemens AG 2015