SIEMENS
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Siemens NC 62 · 2016
Feed motors
SIMOTICS S servomotors for SINAMICS S120
SIMOTICS S-1FT7/1FK7
> Built-in holding brakes
6
■
Overview
Many drives need a holding brake with an emergency stop
function for safety reasons or to meet process requirements.
The permanent magnet or spring-loaded single-surface brakes
used on the 1FT7/1FK7 motors function according to the closed
circuit principle The magnetic field of the permanent-magnet
exerts a tension on the brake anchor plate, i.e. in a condition of
zero current, the brake is closed and the motor shaft thereby
stopped. When the rated voltage of 24 V DC ± 10 % is applied
to the brake, current flows through the coil and produces a
counter-field that cancels the pull of the permanent-magnet,
causing the brake to release.
With the spring-loaded single-surface brake version, the brake
is operated by the compressive force of the spring rather than
the permanent magnet.
In the event of an emergency stop or power outage, approxi-
mately 2000 braking operations can be performed with maxi-
mum switched energy without causing excessive wear on the
holding brake (condition: maximum external moment of inertia =
moment of inertia of motor and
n
max
type-specific).
The holding brake is not
an operational brake.
In order to avoid switching overvoltages and any related effects
on the plant environment, the brake cables must be connected
externally with a varistor. The connection is made via the power
connector or the terminal box.
When connected to the SINAMICS S120 drive system, this
overvoltage protection is provided by the SINAMICS system.
■
Technical specifications
Motor
Built-in holding brake
Shaft
height
SH
Type
Holding
torque
1)
Direct
current
Opening time
with varistor
Closing time
with varistor
Moment of
inertia
Maximum switched
energy per brake
operation
from
n
= 3000 rpm
Nm
(lb
f
-ft)
A
ms
ms
10
-4
kgm
2
(10
-3
lb
f
-in-s
2
)
J
1FT7 motors with permanent-magnet brake, without backlash, and 1FK7 motors with option N24
36
1FT703
3 (2.21)
0.3
60
25
0.12 (0.11)
30
48
1FT704
8 (5.9)
0.6
90
30
0.87 (0.77)
270
63
1FT706
18 (13.3)
0.8
150
50
2.84 (2.51)
880
80
1FT708
48 (35.4)
1.0
220
65
15.4 (13.63)
1900
100
1FT710
85 (62.7)
1.6
250
70
27.6 (24.43)
5300
132
1FT713
140 (103)
1.8
350
70
51.0 (45.14)
9800
1FK7 Compact/High Dynamic/High Inertia motors with permanent magnet brake, without backlash
10
1FK701
0.4 (0.3)
0.3
30
20
0.019 (0.02)
2
28
1FK7022
1.0 (0.7)
0.3
30
20
0.07 (0.06)
8
36
1FK703
1.9 (1.4)
0.3
50
30
0.098 (0.09)
40
48
1FK704
4.0 (2.95)
0.5
70
30
0.32 (0.28)
150
63
1FK706
13 (9.59)
0.8
100
50
0.99 (0.88)
380
80
1FK708
22 (16.2)
0.9
200
60
3.28 (2.90)
1400
100
1FK7100
23 (16.96)
1.0
300
70
7.5 (6.64)
3380
100
1FK7101
1FK7103
1FK7105
43 (31.72)
1.0
300
70
7.5 (6.64)
3380
1FK7-DYA geared servomotors and 1FK7 helical/bevel/parallel shaft/worm geared motors
36
1FK7032
1.3 (0.96)
0.4
50
30
0.08 (0.07)
17
48
1FK704
3.2 (2.36)
0.6
70
30
0.72 (0.64)
74
63
1FK706
13 (9.59)
0.8
100
50
2.25 (1.99)
400
80
1FK7080
1FK7083
10 (7.38)
22 (16.2)
0.7
0.9
100
200
50
60
3.1 (2.74)
8.6 (7.61)
400
1400
100
1FK7100
22 (16.2)
0.9
200
60
8.6 (7.61)
1400
100
1FK7101
1FK7103
1FK7105
41 (30.2)
1.0
300
70
13.5 (11.96)
3000
1)
The holding torque is the highest permissible torque with which the closed brake can be loaded in steady-state operation without slip
(holding function when motor is stationary).
© Siemens AG 2016