Bacharach 19-7043, 19-7038 manual Operation, Power ON/OFF, Zeroing the Instrument

4 OPERATION

To operate the Dioxor II, you simply . . .

•Set its POWER switch to ON,

•Wait for the instrument to warm up (approx. 1 minute),

•Zero the display (if necessary),

•Take a gas sample.

Detailed operating procedures are presented below:

4.1 Power ON/OFF

Turn on the instrument by sliding its POWER switch to ON. Observe that when power is first applied, all numerical LCD segments are tested for

5-15 seconds; after which, the LCD shows the detected SO2 level. (A minus sign may appear during power up as the sensor stabilizes.) Turn off the instrument by sliding the POWER switch to OFF.

Important! When storing the instrument for extended periods of time, remove the batteries and ensure that the POWER switch is OFF. The OFF position places a short across the SO2 sensor, thus keeping the sensor from being destabilized while not in use.

4.2 Zeroing the Instrument

After being turned on and warmed up for at least 1 minute, the instrument should indicate 000 ±5 ppm in fresh air. If the instrument needs to be zeroed, proceed as follows:

1.Ensure that the instrument is sampling air that is free of sulfur dioxide.

NOTE: An indication that the instrument was not zeroed in fresh

air is when a large negative SO2 display appears when the instrument is moved into another area.

2.Using a 1/8" flat-blade screwdriver, turn the ADJUST potentiometer until the LCD shows 0 ppm. The display shows negative numbers for

zeroing purposes. An instrument can be considered zeroed with a display bounce of up to ±3 ppm.

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