Siemens SIMODRIVE POSMO A User Manual page 42

02.99 06.05
Regenerative Depending on the type of power supply, the following possibilities are
feedback available to provide regenerative feedback protection when the motors
protection for brake:
48 V supply
Non–regulated 48 V power supply (transformer, rectifier)
(300 W motor)
The regenerative feedback protection depends on the following factors:
S
S
S
Regulated 48 V power supply (SITOP power)
S
SITOP modular or
24 V
48 V
L+
M
Fig. 2-12 Example: Regenerative feedback protection with diode and
capacitor
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SIMODRIVE POSMO A User Manual (POS1) – 08/2013 Edition
– Total current through the PMM:
– Pulse load at the pulsed resistor:
– Continuous power through
the pulsed resistor:
In this application, a maximum of only 3 motors could be braked
once per second or over a longer periods of time without the I
monitoring responding and causing the unit to go into a "fault" condi-
tion (3 x 3 Ws /1s = 9 W < 10 W).
Effective total moment of inertia
Coincidence factor
Power supply used (output rating)
Regenerative feedback protection with diode and capacitor
An example is shown in Fig. 2-12 where up to 3 drives can be oper-
ated under the following conditions:
– Effective overall moment of inertia = 1 motor moment of inertia
– Coincidence factor = 1
– Braking from rated speed in S3 duty
2 SITOP power
Diode (adapt the current load capacity
to SITOP, if required, use a heatsink)
L+
48 V
to the
remaining
M
system
2 Installing and Connecting–Up
2.2 Electrical system requirements
5 x 5 A = 25 A
5 x 3 Ws = 15 Ws
15 Ws/1s = 15 W
M SIMODRIVE
POSMO A, 1
Elko
w 15000 μF/100 V
2
t
SIMODRIVE
POSMO A, 3
2-41
2