PROBE
RESET
A/M
SAMPLE
The Probe button is only used in the manual
mode, and tells the microprosessor how many physi-
cal lengths of probe are attached to the unit. This
is done to mathematically calculate how long it will
take to get a sample from the boot to the sensing
elements.
The Reset button allows the unit to remain pow-
ered but clears all the internal logic circuitry. The
device goes through its zeroing routine to deter-
mine a new baseline. This button is preferred to
turning the device off and back on in that it main-
tains power to the sensing elements, thus main-
taining sensor stability. Only press this button in a
zero tracer gas environment.
MODE: this button controls what is being dis-
played on the LCD. By default the unit is in auto-
matic mode and will constantly show what the sens-
ing elements have detected in both concentration
as well as time. If the unit is placed in the manual
mode, the device will continue to draw in samples
as normal. However, when the sample button is
pressed, the LCD no longer shows time, but will only
show what the sensors are detecting at that one
particular moment of time.
The sample button tells the microprocessor to
take one reading. Upon pressing this button, the
microprocessor looks at the probe length selected
and calculates how long it should take for the sample
to get to the detector, takes the sample, then dis-
plays the result.
This is a one shot button, meaning that for every
sample needed, the sample button must be re-
pressed.
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