4
4 OPERATION
To operate the Monoxor 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 fi rst applied, all
numerical LCD segments are tested for 5–15 sec-
onds; after which, the LCD shows the detected CO 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 CO 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 instru-
ment 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 Carbon
Monoxide.
NOTE: If the instrument was zeroed in an area where CO was
present, a large negative CO display appears.
2. Using a 1/8" fl at-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.
