Siemens SIMATIC S7-300 Manual page 293

Table 11-4 Diagnostic interrupt, continued
Byte.
Bit
0.2, 0.3 External channel errors
8.2 Erroneous pulses, incremental encoder or zero reference mark missing
(8092) (8092)
Cause Encoder monitoring circuit has discovered erroneous pulses
In "reference point operation" operating mode, no zero reference mark came
within one encoder revolution after the reference point switch was passed.
Number of pulses per encoder revolution (MD13) incorrectly input
Encoder faulty: does not deliver the specified number of pulses
Zero reference mark faulty or missing altogether
Pulse length of zero reference mark shorter than 1.25 µs
Interference on the measurement system cable
Effect
Elimina- Enter MD13 correctly
tion
Check encoder and measurement system cable
Observe limit values
Observe rules on shielding and grounding
Using the MD20, monitoring can be temporarily skipped, at the responsi-
bility of the owner/operator.
8.3
Voltage monitoring, encoder
(8093) (8093)
Cause Short-circuit in encoder supply cable (5 V incrementally, 24 V SSI)
Failure of module internal encoder supply unit
Effect
Elimina- Check connections
tion
Replace FM 354 if encoder cable ok
Using the MD20, monitoring can be temporarily skipped, at the responsi-
bility of the owner/operator.
8.7 For operator control errors, see Table 11-5
(8097)
Note: (xxxx) value = Hexadecimal notation in diagnostic buffer
FM 354 Servo Drive Positioning Module
Error message,
error analysis and elimination
Error response: "Everything Off", as in Table 11-2
Troubleshooting
Message/
Display
SF SF
DC5V
DIAG
11-13