Disconnection Detection Signal (Xc) Has Turned On; Measured Temperature Value Cannot Be Read; Measured Temperature Value Is Abnormal - Mitsubishi Electric Q64RD User Manual

8 TROUBLESHOOTING

8.2.7 Disconnection detection signal (XC) has turned on

Check whether RTD is connected securely or not.
Check for loose terminal screws.
Check the connected RTD for wire break.
Check whether the channel where no RTD is connected is specified
for conversion enable.

8.2.8 Measured temperature value cannot be read

Check whether the used channel has been set for conversion
disable.
Check whether the programmable controller CPU is set for STOP.

8.2.9 Measured temperature value is abnormal

Check whether the RTD differs from the one specified.
Check whether the connected RTD is connected reversely.
Check for noise in the RTD input.
Check whether conversion is made with another RTD specified after
setting of the offset/gain value.
8 - 4
Check Item
Check Item
Check Item
Connect it securely.
Retighten the terminal screws within the specified torque range.
Make continuity check on the RTD, and replace it if its wire is
broken.
Check the channels which are specified for conversion enable and
the channels where RTDs are connected, and make the conversion
setting correctly.
Set it for conversion enable in sequence program.
Set the programmable controller CPU for RUN.
Set the RTD connected to the switch 1 in the intelligent function
module switch setting.
Connect the RTD correctly.
Check influence from the ground and adjacent devices, and take
action to prevent noise.
Make offset/gain setting again for the current RTD.
MELSEC-Q
Remedy
Remedy
Remedy
8 - 4