Extech Instruments CO80, Руководство пользователя

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CO80 V3.1 04/06 22
4.7.
Switching Off
The CO80 has been designed to provide maximum protection to its
components by purging the sensors upon shutdown. If the unit is left for
15 minutes, the unit will automatically switch off if the CO reading is below
20 ppm. However, if there is more than 20 ppm CO present, the
instrument will continue to purge the sensor with clean air until the reading
falls below 20 ppm before turning itself off.
4.7.1 In Normal Mode
When all appropriate readings have been taken, the probe should be
removed from the flue, and the unit switched off by pressing the “
On/Off
”
key. The close down routine purges unwanted flue gases from the
instrument, extending its operational life, and prepares the instrument for
the next set of measurements.
4.7.2 Power Off In High CO Levels
If the unit is turned “
OFF
” after the carbon monoxide sensor has been
exposed to high levels of CO gas, the display will show the following, with
the number “
30
” flashing:
Whilst this display is shown, the “
On/Off
” key can be pressed to return to
the previous screen.
The instrument will
commence a 30-second
purge routine, such that
after 7 seconds, the
display will look as
shown
In this mode, the unit continues
to pump clean air past the CO
sensor. As soon as the CO level
falls below 20 ppm the unit will
automatically start its 30-second
countdown and then turn off.