Siemens SIMATIC FM 453, Manual

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FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
If MD20 = 0 is input, all monitoring functions are active.
Individual monitoring functions can be inactivated by entering 0 in the desig-
nated bit of MD20.
You can deactivate the error messages using the single function “parking
axis” (see Section 9.3.2).
Table 9-10 Error Diagnostics – Incremental encoder
Diagnosis Cause Error Message
Cable break monitoring Signals of one track pair (A, A / B, B / N, N)
do not behave as negations of one another. The FM 453 responds with a diagnostic
interrupt, external channel error (see Trou-
bleshooting, Table 11-4)
Pulse monitoring
S
Signal track missing
S
Actual no. of pulses/rev
0
MD13
S
No signal change to a track pair
S
If the contents of the missing-pulse
memory exceed a value of 7, a diag-
nostic interrupt, external channel error
is output (see Troubleshooting, Table
11-4).
S
The missing-pulse memory is cleared
with the control signal “Restart” .
Note:
For encoders with non-cyclic zero pulse
→
switch pulse monitoring in MD20 OFF.
In Reference-Point Approach mode, no
zero pulse is recorded after leaving the
reference-point switch within the path as de-
fined in MD11, 12. Effect:
S
Encoder cannot be synchronized.
S
On leaving the reference-point switch
in Reference-Point Approach mode,
the FM 453 will travel no more than
the distance of one encoder revolution
(MD11), and needs the deceleration
distance from the reducing speed.
Voltage monitoring Encoder power failure Diagnostic interrupt, external channel error
(see Troubleshooting, Table 11-4)
!
Warning
Hardware monitoring functions should be skipped only for test purposes,
since positioning errors may destroy the machine.
Exception:
Pulse monitoring for encoders with non-cyclic zero pulse.
See Section 4.5.
Monitoring/Error
Diagnostics
Encoder
Connection
Description of Functions