Siemens SIMATIC SIMOSTEP 1FL3041 Functional Description page 49

02.05
3-phase stepping
motors with holding
brake
!
24 V
24 Ω min. 6 W
for 1FL304X
18 Ω 8 W
for 1FL306X
U Brake
3
0 V
Figure 9-5 Example of a circuit to reduce dissipation of the holding brake
Terminal assigment
2
3
1
24 VDC
non-polarized
© Siemens AG 1998 All Rights Reserved
FM-STEPDRIVE/SIMOSTEP (FB)
The holding brakes are used to hold the motor in position when the motor
current is switched off. In cases of emergency, e.g. power failure or
EMERGENCY OFF, they stop the drive, thus contributing to the safety of
the system. The brakes are required for applications in which gravity
forces play a role, e.g. Z-axes in handling systems.
Caution
In order to ensure reliable functioning of the Z axes with holding brakes,
the statical loading torque should not exceed a maximum of 25% of the
motor holding torque.
Function
The holding brakes are designed as electromagnetic spring pressure
brakes. In order to disengage the brake, it must be electrically excited
when the motor current is switched on. To avoid high temperature of the
brake, the current for the brake is reduced to holding voltage when the
brake is still disengaged (see figure 9-5).
1 N 4001
4700 µF/18 V
for 1FL304X
+
6800 µF/18 V
for 1FL306X
Performance data of holding brake
Specifications
Nominal voltage
(power supply via pin 1 and 2)
Holding torque
Power consumption
Moment of inertia
Switching times
On (disengage brake)
Off (engage brake)
9 SIMOSTEP specifications
U [V]
3
24
Starting voltage
75%
50%
90
24 V
6 Nm
24 W
2
0,2 kgcm
35 ms
15 ms
Holding voltage
Motor-size
110
24 V
16 Nm
32 W
2
0,35 kgcm
65 ms
15 ms
t
9-5