| Analog output reading is unchanging and appears incorrect. |
Analog output is in error state. |
Remove the cause of the error state and the analog output recovers
its normal function. |
| Probe outputs stars "****" on serial line instead of measurement
data. |
Incorrect supply voltage. |
Check the power supply. Check the active errors using the
ERRS command on the serial line. |
| Unsuitable operating environment. |
Verify that the operating environment is within specified operating limits. |
| Unable to access probe on RS-485 line. |
Incorrect wiring. |
Check that the RS-485 connection is wired correctly. |
|
Power cycle or reset the probe and try again. |
|
Probe in POLL mode with unknown address. |
Issue the ?? command to make the probe output its information.
Then use the OPEN command to open a line to the probe’s
address. |
| CO2 measurement not working. |
Condensation on the sensor. |
Remove the PTFE filter and check if condensation has formed on the sensor. If yes, dry out the condensation with instrument air and insert a new dry filter. Keep the probe powered and operating to prevent re-occurrence. |