Omron CJ1W-SCU22, Руководство по эксплуатации, Страница: 328 / 478

9 Troubleshooting and Maintenance
9-50
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Event name Parity Error Event code 846B 0000 hex
Meaning A parity error occurred.
Source PLC Function Module Source details CJ-series Unit Detection
timing After serial com-
munications start
Error attributes Level Observation Recovery --- Log category System
Effects User program Continues. Operation Not affected.
System-defined
variables Variable Data type Name
None --- ---
Cause and
correction Assumed cause Correction Prevention
In Serial Gateway Mode or Protocol
Macro Mode:
• The reception circuits in the Serial
Communications Unit are faulty.
• A transmission error occurred due
to noise or other factors.
• Perform a loopback test in the serial
communications mode and check
the transmission lines. If an error
occurs during testing, replace the
Serial Communications Unit.
• Implement noise countermeasures.
Increase the setting for the number
of resends in the device that sent
the command. If required, perform
retry processing for communica-
tions.
Perform countermeasures in
advance.
During Loopback Test
• Loopback test jig failure.
• Noise
• The communications circuits in the
Serial Communications Unit are
faulty.
• Correct any mistakes in wiring the
loopback test jig.
• Implement noise countermeasures.
• Replace the Unit.
• Check the wiring of the loopback
test jig.
• Use the Unit away from sources of
noise. Implement noise counter-
measures.
Attached
information Attached information 1: Port number where error was detected
Precautions/
Remarks None