Error Processing - Omron CJ Series Operation Manual

3-1-12 Error Processing

Conversion Data Does Not Change
The gain for span adjustment is set to 0.
The input type setting is incorrect.
An input device is faulty, input wiring is incorrectly
wired, or wiring is disconnected.
The minimum and maximum values for process value
scaling are either the same or are set too close
together.
Values are Not Converted as Intended
The zero/span adjustment values are incorrect.
There is an error in the scaling settings.
A resistance thermometer's input wiring is incorrect.
The compensating wire is too long and affecting opera-
tion.
The input type or process value scaling setting is incor-
rect.
Cold junction sensor is not operating.
No compensating wire is being used, or another type of
compensating wire is being used.
The input wiring is faulty. (The polarity is incorrect in the
thermocouple or compensating wire.)
Conversion Values are Unstable
The input signals are being affected by external noise.
The process value is being scaled beyond the Unit's
resolution.
CJ-series Analog I/O Units Operation Manual for NJ-series CPU Unit(W498)
Probable cause
Probable cause
Probable cause
3 Isolated-type Universal Input Units
Remedy
Set the gain for span adjustment to a value other than
0.
Check and correct the input type setting.
Check whether the input value is changing.
Check for faulty or disconnected wiring.
Check whether a sensor error has been detected.
Set the minimum and maximum process value scaling
values correctly.
Remedy
Check and correct the zero/span adjustment settings.
Check and correct the scaling settings.
Check and correct the input wiring.
Use a thicker thermocouple compensating wire.
Check the input type or process value scaling settings
and correct if necessary.
Check the Cold Junction Sensor Error Flag.
Use the correct thermocouple compensating wire.
Check and correct the input wiring.
Remedy
Change the connection paths of the input signal lines.
(Separate them from sources of noise or use shielded
twisted cable.)
Insert a 0.01-µF to 0.1-µF ceramic capacitor or film
capacitor between the input's (+) and (−) terminals.
Reduce the process value's scaling value.
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