23
11. Troubleshooting
If any malfunctions occur, refer to the following items after checking the power of the controller.
11.1 Indication
Problem
Presumed cause and the action
The PV/SV display is
indicating [
]
• Control output OFF function is working.
Press the
key for approx. 1sec to release the function.
[
] is flashing
on the PV/SV display
• Thermocouple or RTD may be burnt out.
How to check whether the sensor is burnt out
[Thermocouple]
If the input terminals of the instrument are shorted, and if a value around
room temperature is indicated, the instrument is likely to be operating
normally, however, the sensor may be burnt out.
[RTD]
If approx. 100
resistance is connected to the input terminals between
A-B of the instrument and between B-B is shorted, and if a value around
0
(32 ) is indicated, the instrument is likely to be operating normally,
however, the sensor may be burnt out.
• Check whether the thermocouple or RTD lead wire is securely mounted to
the instrument terminal.
[
] is flashing
on the PV/SV display
• Check whether the polarity of thermocouple or compensating lead wire is
correct.
• Check whether codes (A, B, B) of the RTD agree with the controller
terminals.
Ensure that they are wired properly.
The indication of the
PV/SV display is
irregular or unstable.
• Check whether the sensor input and temperature unit (
or
) setting
are correct.
Set the sensor input and the temperature unit properly.
• Sensor correction value is unsuitable.
Set it to a suitable value.
• Sensor specification is improper.
Set the sensor specification properly.
• AC may be leaking into the sensor circuit.
• There may be equipment that interferes with or makes noise near the
controller.
Keep equipment that interferes with or makes noise away from the
controller.
11.2 Key operation
Problem
Presumed cause and the action
Settings (SV, P, I, D,
proportional cycle, alarm,
etc.) are impossible.
The values do not change
by the
or
key.
• Set value lock (Lock 1 or Lock 2) is selected.
Release the lock selection.
• During auto-tuning or auto-reset.
Cancel auto-tuning.
Auto-reset ends in 4 minutes after it has started.
The setting indication
does not change within
the input range even if
the
or
key is
pressed, and new values
are unable to be set.
• SV high limit or SV low limit may be set at the point where
the value does not change.
Set it to a suitable value during Auxiliary function setting mode 1.
