SenTech IR-SNIF-1, Инструкция по установке и эксплуатации

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The 1/4 inch tubing should be long
enough to connect to the sample
inlet and extend into the bottom of
the sample container. Because
refrigerants are heavier than air,
pulling the sample from the bottom of
the container will ensure introduction
of the refrigerant into the selected
zone.
a) Gaseous Refrigerants: Insert a
refrigerant fill hose into the container
opening. Crack the valve for a
second or less so that a small squirt
of refrigerant enters. Keep in mind
that the monitor reads in PPM (parts
per million) and a tiny amount of gas
will
make a relatively high
concentration sample. Pull out the
hose,
and loosely close the
container.
b) Liquid Refrigerants: Open the
container slightly and put in a few
drops of liquid refrigerant. Loosely
close the container and allow time
for the refrigerant to gasify. A bag
will expand some as the liquid
evaporates.
Caution: Do not close a
rigid
sample container
tightly, because refrigerants
expand and can create
pressure. Do not allow
pressure to build up in the
sample container.
Step 3: Manual measurement of
sample. Switch the monitor to
manual override. Manual Override is
accessed by pressing the "ENT"
(enter) key on the front panel display
of the monitor. Press the "3" key to
enter Manual Override. Place the
1/4 inch tube into the sample
container and connect it to the
sample
inlet to simulate a
concentration of refrigerant in the air.
Caution: Never connect a
pressurized
refrigerant
bottle directly to the
monitor. The unit is
designed to operate only at
atmospheric
pressure.
Doing so can damage the
unit.
After approximately 5 seconds, the
PPM reading should start to rise.
Within 30 to 45 seconds, the PPM
level should level off. A sample
prepared as described in step 2
should easily contain more than 150
PPM. If the PPM reading does not
rise above the highest alarm setting
in the monitor, repeat the sample
preparation procedure with a larger
amount of refrigerant. Readings of
150 or higher indicate a successful
test of the monitor's ability to sense
refrigerant. Disconnect the sample
from the monitor and save for the
next step. The sample container
should now have a measured
concentration of
refrigerant greater
than the highest alarm level. This
will be used to test the end-to-end
performance of the system in the
next step.
Once the sample tube has been
disconnected from the monitor, the
readings should fall slowly down to
at or near zero PPM. When the
PPM level reaches near zero, press
the "ENT" (enter) key to exit Manual
Override and return to normal
operation.