Siemens SIMATIC S7-1500 Manual page 80

Diagnostic alarm
Invalid transition of A/B
signals
RS422/TTL error
SSI encoder error
Overtemperature
No longer available as of module version V1.3. This case is then taken into account by the diagnostic interrupt "Supply
1
voltage missing".
Technology module TM PosInput 2 (6ES7551-1AB00-0AB0)
Manual, 06/2018, A5E03982218-AB
Error Meaning
code
500
Time profile of signals A and B of the
•
H
incremental encoder does not meet
certain requirements (relative phase
shift of the two signals is too small)
Possible causes:
•
– Signal frequency too high
– Encoder faulty
– Process wiring faulty
502
Error at connection of the RS422 en-
•
H
coder, TTL encoder or SSI absolute
encoder
Possible causes:
•
– Wire break
– No encoder connected
– Cable too long
– Short circuit
– Overload
– External voltage
– Overtemperature
– Parameter assignment error
503
Error at SSI absolute encoder connec-
•
H
tion
Possible causes:
•
– Wire break
– Cable too long
– Frame error (error of the start bit or
stop bit)
– Parity error
– Parameter assignment error
506
Short-circuit or overload at the digital
•
H
outputs or outputs of the encoder sup-
ply
Ambient temperature outside specifi-
•
cations
Contamination in the module prevents
•
cooling
Interrupts/diagnostic messages
5.2 Diagnostic alarms
Remedy
Check process wiring
•
Check encoder/sensor
•
Check parameter assignment
•
Check process wiring
•
Check encoder/sensor
•
Check parameter assignment
•
Check process wiring
•
Check SSI absolute encoder
•
Check parameter assignment
•
Check process wiring
•
Improve cooling
•
Check connected loads
•
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