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auto-start routine / auto-zero routine
An auto-start routine / auto-zero routine will have to be run when putting the unit into operation or if
the temperature setpoint is altered by more than 1°C.
To ensure that there is only air, i.e. no CO
2
in the chamber before the auto-start routine is acti-
vated, ventilate the chamber by opening all doors.
The auto-start can only be activated if the doors are open for at least 30 s.
The indicator lamp "auto-start" (page 19 (17)) indicates when the auto-start routine is running.
Calibration can take up to 5 hours, especially if the unit is cold.
If the unit door is opened during the auto-start, the auto-start routine / auto-zero routine restarts
automatically after the unit door is closed.
On resumption of the power supply after a power failure, the auto-start routine / auto-zero routine
is also restarted.
Instruction
Entry / Keys / Remarks
Display / Remarks / Status
Open unit doors for at least
30 seconds
All display segments flash
Adjust or check the set-
points
Refer to pages 20
Activate auto-start
&
Indicator lamp (page 19 (17)) "auto-
start" flashes
Press for approx. 5 seconds
Close all unit doors
Temperature reads "Actual value"
CO
2
reads " 0.0"
O
2
reads "21.0" (optional)
rel. humidity reads "Actual value"
The unit is set to the temperature and relative humidity setpoints. When temperature and relative hu-
midity setpoints are achieved consistently, the CO
2
measuring system is automatically calibrated and
the O
2
sensor (optional) is calibrated for 21%.
Indicator lamp (page 18 (17)) "auto-start" goes out.
The auto-zero routine determines the reference value and O
2
sensor (optional) is calibrated.
Gas is admitted until the CO
2
/O
2
setpoints are reached.
The auto-zero routine compensates for zero drift of the CO
2
measuring cell. The auto-zero routine
runs automatically every 6 hours. When the indicator lamp (page 19 (13)) "auto-zero" is flashing,
the auto-zero routine is in progress. If the door is opened or closed during the auto-zero routine,
auto-zero calibration is restarted.
If the auto-start has not been completed after 24 hours at the latest (page 19, indicator lamp (17)
"auto-start" is still flashing), the auto-start will have to be cancelled manually (refer to page 24)
and repeat.
6. OPERATE
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