Teledyne First Responder CG, User Handbook Manual, Page: 16 / 104

2-2
GENERAL INFORMATION FIRST RESPONDER CG - USER HANDBOOK
Fig. 2-1 EXTernal Range
PPM, 0 – 4500 ppm
(CGI mode only)
This range will measure very low levels of gas and indicates
the PPM concentration of gas in air (45 ppm is equivalent
to 0.1% LEL). This sensitive range will take longer than LEL
and Volume Gas to stabilise.
For methane, when the measurement exceeds 4500 ppm,
the instrument autoranges to LEL.
When the PPM range is selected, PPM is displayed in the
top right corner of the LCD. From 0 to 1000 ppm the digital
display resolves to 5 ppm. From 1000 to 4500 ppm the
digital display resolves to 50 ppm. The analogue bar graph
follows in 200 ppm steps. An example of the PPM display
is shown in Figure 2-2.
The detection principle for this range is a catalytic reaction.
Fig. 2-2 PPM Range