WatchGas NEO User Manual page 22

NEO
Photo-ionization Detector
The Time is expressed as Hours/Minutes/Seconds, with
two digits for each. The time is in 24-hour (military)
format. Adjust the time in the same manner as for the date.
5.8.2 DISPLAY
The Display function is used to set LCD contrast and backlight.
The default LCD Contrast is about 50%.
To change the contrast, press the Up or Mode key to increase or decrease the digit's
value, then move the cursor to '√' and press Up to save and exit.
The Backlight can be set as Automatic, Manual or Off. In Automatic Mode the backlight
comes on and stays on in low light conditions. In Manual Mode, pressing the Right or Left
key turns the backlight on for one minute.
5.8.3 PUMP SPEED
The pump can operate at two speeds, low and high, ranging from about 250 to 350 cc/
min with a standard 0.45 µm filter in place, or about 350 to 450 cc/min with the filter
removed. Running at low speed is quieter and conserves a small amount of power. There
is almost no difference in sampling accuracy. High pump speed is recommended for
faster response when using an extension hose to sample, or when measuring heavy
compounds, which tend to have slow response because of adsorption on inlet surfaces.
Use the Right key to enter Pump Speed, then Up or Mode to scroll on the list, Right to
select, and Left to save and exit.
Note that each Pump Speed has its own Stall Threshold.
5.8.3 SET PUMP STALL THRESHOLD
The Pump Stall Threshold is the current-draw setting for a
blocked pump alarm. The default setting is 500 to 800,
depending on model. The actual, real-time pump current
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