MODEL 5081-T
SECTION 10.0
DIAGNOSIS AND TROUBLESHOOTING
Message
Explanation
See Section
OuEr rAnGE
Over range, measurement exceeds display limit
10.8.1
SEnSor FAIL
Bad sensor, sensor current is a large negative number
10.8.2
CAL Error
Calibration error, sensitivity (nA/ppm) is too high or too low
10.8.3
nEEd 0 CAL
Sensor needs re-zeroing, reading is too negative
10.8.4
rtd FAIL
Bad temperature reading
10.8.5
TEMP HI
Temperature reading exceeds 275°C when auto temp is selected
10.8.5
TEMP LO
Temperature reading is less than -25°C when auto temp is selected
10.8.5
SenSE OPEn
Sense line is not connected
10.8.6
OFFSEt Err
Zero offset during standardization exceeds programmed limit
10.8.7
FACt FAIL
Unit has not been factory-calibrated
10.8.8
CPU FAIL
Internal CPU tests have failed
10.8.9
ROM FAIL
Internal memory has failed
10.8.9
AdC Error
Analog to digital conversion failed
10.8.10
10.8.1 OuEr rAnGE and AMP FAIL.
These error messages appear if the sensor current is too high. Normally, excessive sensor current implies that the sensor
is miswired or the sensor has failed.
1. Verify that wiring is correct and connections are tight. Be sure to check connections at the junction box if one is being
used. See Section 3.0.
2. Replace the sensor membrane and electrolyte solution and clean the cathode if necessary. See the sensor instruction
sheet for details.
3. Replace the sensor.
10.8.2 SEnSor FAIL.
Bad sensor means that the sensor current is a large negative number.
1.
SEnSor FAIL
may appear for a while when the sensor is first placed in service. Observe the sensor current (go to
SEnSor Cur
under the diagnostic menu). If the sensor current is moving in the positive direction, there is probably
nothing wrong and the error message should soon disappear.
2. Verify that wiring is correct. Pay particular attention the anode and cathode connections.
3. Verify that the transmitter is configured for the correct measurement. Configuring the measurement sets (among other
things) the polarizing voltage. Applying the wrong polarizing voltage to the sensor can cause a negative current.
4. Replace the sensor membrane and electrolyte solution and clean the cathode if necessary. See the sensor instruction
sheet for details.
5. Replace the sensor.
10.8 TROUBLESHOOTING WHEN A FAULT OR WARNING MESSAGE IS SHOWING
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