5 – Preventive maintenance
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8. Reset any alarm signals on the central unit.
Adjustment of gas sensitivity
This procedure takes place after the zeroing stage:
1. Inhibit any alarm signals on the central unit.
2. Place the calibration shroud on the detector head (Figure 17, "A").
3. Connect the calibration shroud to the standard gas bottle "D" by using a
flexible hose "B".
4. Open the valve on the standard gas bottle "C" (flow rate 30 to 60 litres/hr).
5. After the measurement has stabilized (approx. 2 minutes), read the display of
the central measuring unit.
6. Adjust "S" on the measuring unit in order to display the desired value.
7. Close valve "C" on the bottle and remove the calibration shroud "A".
8 . Walt for the measured signal to return to zero and reset the alarm signals on
the central unit.
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Figure 17 : Sensitivity adjustment (OLC100).