User's Guide

POLI User’s Guide
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5.2.1 Editing Parameters & Selecting Sensors
There are a few basic ways to edit parameters, select sensors, and perform other activities
in the POLI. The actions performed by pressing keys always match 1-to-1 with the boxes
along the LCD bottom and the two keys. Some parameters are edited by scrolling and
selecting individual items (black bars behind white text act as highlighters). Some include
a choice via ‘radio keys’ where only one item in a list can be selected, while other menus
use boxes for you to ‘check’ with an ‘X’ and these allow for multiple items in a list to be
selected. In all cases of editing, you can save or undo your choice.
5.2.2 Calibration
Use this menu to perform zero or span calibration for one or more sensors, and change
the gas concentration values equals to that of gas cylinders used in zero or span
calibration.
5.2.2.1 Air (Zero) Calibration
A zero calibration should precede a span calibration.
The selected sensors are shown on the screen. Start a multiple zero test by pressing
[+/OK]. If you do not want to perform a test, press [ /↓].
Zero calibration is to set the base line for the calibration curve, it is done in clean air with
20.9% oxygen. You can calibrate several sensors simultaneously and can also select one
or several sensors individually for zero calibration. This procedure determines zero points
of most sensors.
At the Calibration menu, select ‘Fresh Air’ by pressing [+/OK] once to enter fresh air
calibration. After a timer countdown, the zero calibration is completed. The LCD shows
the sensor names and indicates whether each calibration passed or failed, followed by the
sensor readings. Note: You can abort the calibration at any time during the countdown by
pressing [ /↓].
Note: You can abort a zero calibration by pressing [ /↓] once testing has started.
When the zero calibration is done, the Calibration Results screen is shown with either
‘Pass’ or ‘Fail’ shown. A zero calibration should precede a span calibration.