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12. Troubleshooting
If any malfunctions occur, refer to the following items after checking that power is being supplied to
the controller.
12.1 Indication
Problem
Possible Cause
Solution
[
] is indicated
in the PV Display.
Internal non-volatile IC
memory is defective.
Cancel the error code by pressing the
key,
and perform data clearing. (p.92)
If the problem is not still solved, contact our
agency or us.
[
] is indicated
in the PV Display.
Data writing (in non-volatile
IC memory) error when
power failure occurs.
Cancel the error code by pressing the
key,
and perform data clearing. (p.92)
PV and [
] are
alternately indicated
in the PV Display.
Overscale.
PV has exceeded Input range
high limit value (scaling high
limit value for DC voltage,
current inputs).
Check the input signal source.
PV and [
] are
alternately indicated
in the PV Display.
Underscale.
PV has dropped below Input
range low limit value (scaling
low limit value for DC voltage,
current inputs).
Check the input signal source and wiring of input
terminals.
PV has exceeded the
Indication range and Control
range.
Check the input signal source.
Burnout of thermocouple,
RTD or disconnection of DC
voltage (0 to 1 V DC)
Replace each sensor.
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
of 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.
[DC voltage (0 to 1 V DC)]
If the input terminals of the instrument are
shorted, and if a scaling low limit value is
indicated, the instrument is likely to be operating
normally, however, the signal wire may be
disconnected.
[
] and
[
] are
alternately indicated
in the PV Display.
Check
whether
the
input
terminals of
thermocouple,
RTD or DC voltage (0 to 1 V
DC) are securely mounted to
the instrument input terminals.
Connect the sensor terminals to the instrument
input terminals securely.
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]