WatchGas NEO User Manual page 16

D e t e c t i o n D e t e c t i o n
7.1.4 3-POINT CALIBRATION
Normally, a 2-point calibration gives adequate linearity in PID
response. A 3-point calibration (Zero, Span 1 and Span 2) can be
enabled for more accuracy, particularly in the high concentration
range above about 500 ppm.
To set 3-point or 2-point calibration:
OK
Ent Esc
1. Press or
OK
Ent Esc
OK
Ent Esc
2. Press to continue.
3. Press to save and exit
OK
Ent Esc
Below is the list of default 1st and 2nd Span points when using isobutylene for calibration.
These settings
NEO Model
MP181
MP182
MP184
MP185
MP186
NEO Photoionization Detector
to select the desired option.
Span 1
100 ppm
100 ppm
10 ppm
10 ppm
5 ppm (benzene)
Span 2
1000 ppm
5000 ppm
1000 ppm
1000 ppm
N/A
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User Manual