62
Error Detection
When an error occurs in an input or in the Unit, details of the error are reported to
the Data Setting Console and input relays.
Sensor Input Errors
Display
Error name
Output status after
error
Cause
Remedy
ser1
Loop 1 sensor error
Control output:
The transistor output or
voltage output turns OFF
or the current output falls
below 2 mA.
Alarm output:
The alarm is output
Reading is
±
10%FS out
of sensor measurement
range (i.e., 10%FS
below the lower limit or
10%FS above the upper
limit).
Broken or incorrect
Check the sensor wiring.
Replace the sensor.
Replace the Unit.
Correctly set switch
SW203-4.
ser2
Loop 2 sensor error
The alarm is out ut
assuming the input is
±
10%FS.
Broken or incorrect
sensor wiring
Defective sensor
Defective Unit
SW203-4 is OFF (Loop
2 enabled) but no sensor
connected to Loop 2
serr
Cold junction
compensating circuit
error
Control output:
The transistor output or
voltage output turns OFF
or the current output falls
below 2 mA.
Alarm output turns OFF.
Abnormality in cold
junction compensating
circuit. Applies to
thermocouple type only.
Replace the Unit.
Data Setting Console
When a sensor error occurs, one of the codes above and the detected tempera-
ture are displayed alternately.
If a Loop 1 sensor error
ser1
and a Loop 2 sensor error
ser2
occur simulta-
neously,
ser1
is displayed preferentially. Even if a sensor error is detected in one
Loop, the other Loop continues to operate normally. Control operation restarts
automatically five seconds after the cause of the error is corrected.
The bits shown in the table below are set to 1 when a relay input error occurs.
Wd (n+8), bit 14
Loop 1 sensor error
Both bits = 1 after a cold junction
i
i
i
Wd (n+9), bit 14
Loop 2 sensor error
j
compensating circuit error.
CT Input Overflow
Display
Error name
Cause
Remedy
ffff
CT input overflow
The detected heater
current exceeds 5.5 A.
Check the CT and
heater wiring.
The display shown in the table above will appear if the CT overflow error occurs
when the heater current monitor is selected. The display returns to normal after
the cause of the error is removed.
The bits shown in the table below are set to 1 when the CT overflow error occurs.
Wd (n+8), bit 13
Loop 1 CT overflow
Wd (n+9), bit 13
Loop 2 CT overflow
Heater Burnout Alarm
Display
Error name
Cause
Remedy
HB
indicator lit
Heater burnout
The detected heater
current is below the
heater burnout current
value.
Check the heater
and heater wiring.
Replace heater if
necessary.
Error displayed when an abnormality occurs in the loop currently being dis-
played.
Error Detection
Section 5
electronic components distributor