Troubleshooting - Omron SYSMAC CJ1W-AD04U Operation Manual

Troubleshooting

5-5 Troubleshooting
Conversion Data Does Not Change
Probable cause
The span adjustment value is set to 0. Set the span adjustment value to a value other than 0.
The input type setting is incorrect.
An input device is faulty, input wiring is
incorrectly wired, or wiring is discon-
nected.
The minimum and maximum values for
process value scaling are either the
same or are set too close together.
Value Does Not Change as Intended
Probable cause
The zero/span adjustment values are
incorrect.
There is an error in the scaling set-
tings.
A resistance thermometer's input wir-
ing is incorrect.
The compensating wire is too long and
affecting operation.
The input type or process value scal-
ing setting is incorrect.
Cold junction compensation 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 Inconsistent
Probable cause
The input signals are being affected by
external noise.
The process value is being scaled
beyond the Unit's resolution.
48
The following tables explain the probable causes of troubles that may occur,
and the countermeasures for dealing with them.
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 cor-
rectly.
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.
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.
Countermeasure
Countermeasure
Countermeasure
Section 5-5
Page
P. 34
P. 33
P. 19, P, 36
P. 35
Page
P. 34
P. 35
P. 19
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P. 33, P. 35
P. 39
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P. 19
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P. 35