Siemens SIMATIC FM 453, Manual

Page: 278 / 380

9-78
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
Approach to the target position
Target range (PEH) (MD24)
s
t
Monitoring time (MD25)
t
1
t
2
t
3
Position to be
approached
Upper range
Lower limit
t – time
s – path
PEH – Position reached, stop
b
c
a
Set
Actual
On approach to a position, the monitoring time is activated:
Time Position Monitoring
t
1
(a) After the interpolator reaches the target position, the monitoring time
(MD25) for reaching the target range is started in the CL controller, after
the overtravel in the jolt filter dies down to the target range value (PEH
on setpoint side).
t
2
(b) Before the monitoring time expires, the actual position reaches the target
range. Positioning is completed. A PEH is signaled, and exact matching
is performed by the CL controller.
t
3
(c) After the monitoring time expires, the actual position has not reached the
target range (PEH).
Error message: “PEH Target Range Monitoring” (see Troubleshooting,
Table 11-5, Class 3/No. 64)
MD Designation Value/Meaning Unit
24 Target range 0...1 000 000
[
MSR
]
25 Monitoring time 0 = no monitoring
1...100,000
[
ms], rounded to 2–ms
steps
Following error monitoring
Axis standstill
A message is output on an axis standstill setpoint or deactivated servo enable
if disturbances cause the axis to move out of position.
MD Designation Value/Meaning Unit
26 Stationary range 0...1 000 000
[
MSR
]
Description of Functions