Message
Description
Current value too high
Wrong gas for zero point calibration or sensor element defective. Replace sensor
head.
Current value too small
Wrong gas for zero point calibration or sensor element defective. Replace sensor
head
Current value unstable
Appears when the sensor signal does not reach the zero point within the target time.
Disappears automatically when the sensor signal is stable.
Time too short
The message “value unstable” starts an internal timer. Once the timer has run out and
the current value is still unstable, the text is displayed. The process starts over again.
If the value is stable, the current value is displayed and the calibration procedure is
continued. If the cycle is repeated several times, an internal error has occurred. Stop
the calibration process and replace the sensor head.
Internal error
Calibration is not possible
→
check if burning clean process is completed or interrupt
it manually or check/replace sensor head.
During the calculation phase, the following messages may occur:
If aborting the zero offset calibration, the offset value will not be updated. The sensor head continues
to use the “old” zero offset. A full calibration routine must be conducted to save any calibration
change.
By using the arrow key, select the Gain menu.
Connect the calibration gas cylinder to the sensor head by using the calibration adapter (Fig. 1).
Open the cylinder flow regulator to start allowing the flow which is recommended to be minimum
150 ml/min.
Press Enter to show the value read currently, after some minutes, once the ppm value has stabilized,
press Enter again to start the calibration.
In line 2, during calculation, an underscore runs from left to right and the current value converges to
the set test gas that has been flow.
When the current value is stable and near to the reference value of the set calibration gas
concentration, press Enter for finishing the calculation of the new value.
After the value has been successfully stored, a square appears on the right for a short time = Gain
calibration is finished a new gain offset has been stored with success.
The display automatically goes to the display of the current ppm value.
During the calculation phase, the following messages may occur:
At the end of the calibration procedure exit from the Service Mode.
1. Press ESC
2. Press up arrow until the Service Mode menu
3. Press Enter and Service Mode ON is shown
4. Press Enter and down arrow to change the status from ON to OFF and then press Enter again.
The unit is in Operation Mode and the display green LED is solid.
3.3 Gain Calibration
Message
Description
Current value too high
Test gas concentration > than set value
Internal error
→
replace sensor head
Current value too low
No test gas or wrong test gas applied to the sensor.
Test gas too high
Test gas too low
The set test gas concentration must be between 30% and 90% of the measuring
range.
Current value unstable
Appears when the sensor signal does not reach the calibration point within the target
time. Disappears automatically when the sensor signal is stable.
Time too short
The message “value unstable” starts an internal timer. Once the timer has run out and
the current value is still unstable, the text is displayed. The process starts over again.
If the value is stable, the current value is displayed and the calibration procedure is
continued. If the cycle is repeated several times, an internal error has occurred. Stop
the calibration process and replace the sensor head.
Sensitivity <
Sensitivity of the sensor head < 30%, calibration no longer possible
→
replace sensor
head.
Internal error
Calibration is not possible
→
check if burning clean process is completed or interrupt
it manually
or check/replace sensor head.
Operating Guide | DGS functional tests and calibration procedure
6 | AQ430229665343en-000101
© Danfoss | Climate Solutions | 2022.10
