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124
Handling Errors and Alarms
Section 3-8
3-8-4
Restarting Special I/O Units
There are two ways to restart Special I/O Unit operation after having changed
DM contents or having cleared the cause of an error. The first way is to turn
the power to the PLC OFF and ON, and the second way is to turn ON the
Special I/O Unit Restart Bit ON.
Special I/O Unit Restart Bits
The conversion data becomes 0000 during restart.
If the error is not cleared even after turning the Special I/O Unit Restart Bit ON
and then OFF again, then replace the Unit.
3-8-5
Troubleshooting
The following tables explain the probable causes of troubles that may occur,
and the countermeasures for dealing with them.
Conversion Data Does Not Change
Value Does Not Change as Intended
Conversion Values are Inconsistent
Bits
Functions
A50200
Unit #0 Restart Bit
Turning the Restart Bit for any
Unit ON and then OFF again
restarts that Unit.
A50201
Unit #1 Restart Bit
~
~
A50215
Unit #15 Restart Bit
A50300
Unit #16 Restart Bit
~
~
A50715
Unit #95 Restart Bit
Probable cause
Countermeasure
Page
The input is not set for being used.
Set the input to be used.
The peak value hold function is in
operation.
Turn OFF the peak value hold func-
tion if it is not required.
The input device is not working, the
input wiring is wrong, or there is a
disconnection.
Using a tester, check to see if the
input voltage or current is changing.
---
Use Unit’s alarm flags to check for a
disconnection.
Probable cause
Countermeasure
Page
The input device’s signal range
does not match the input signal
range for the relevant input number
at the Analog Input Unit.
Check the specifications of the
input device, and match the settings
for the input signal ranges.
The offset and gain are not
adjusted.
Adjust the offset and gain.
When using the 4 mA to 20 mA
range, the voltage/current switch is
not turned ON.
Turn ON the voltage/current switch.
Probable cause
Countermeasure
Page
The input signals are being affected
by external noise.
Change the shielded cable connec-
tion to the Unit’s COM terminal.
Insert a 0.01-
µ
F to 0.1-
µ
F ceramic
capacitor or film capacitor between
the input’s (+) and (–) terminals.
---
Try increasing the number of mean
value processing buffers.
Summary of Contents for CJ1W-AD041-V1
Page 3: ...iv...
Page 5: ...vi...
Page 9: ...x TABLE OF CONTENTS...
Page 15: ...xvi...
Page 99: ...76 Handling Errors and Alarms Section 2 8...
Page 191: ...168 Handling Errors and Alarms Section 4 8...
Page 243: ...220 Handling Errors and Alarms Section 5 8...
Page 381: ...358 Handling Errors and Alarms Section 7 10...
Page 385: ...362 Dimensions Appendix A...
Page 395: ...372 Sample Programs Appendix B...
Page 396: ...373 Appendix C Data Memory Coding Sheets...
Page 417: ...394 Data Memory Coding Sheets Appendix C...
Page 425: ......