OPERATION SUMMARY:
1. Insert a particulate filter onto the end of the sample probe and then insert a needle onto the
filter.
2. Press the POWER switch to start unit. No warm up is required.
3. Press the PUMP switch. The pump will come on for approximately 4 to 6 seconds and pull
room air into the sensor through the syringe needle and filter. Note that the meter reading will
decrease slightly when the pump is on. This is normal due to the slight vacuum created in the
sensor when the pump is running. Wait approximately 10-12 seconds for the reading to
stabilize. Room air should give a reading of 20.7 to 21.1 % oxygen.
4. Pierce the food pack with the syringe needle, preferably through a foam rubber septum
(supplied). Depress the PUMP switch and wait for the reading to stabilize (10-12 seconds).
Leave the needle in the package until a stable reading has been obtained.
NOTE: It is difficult to get accurate readings when piercing the bag directly with the needle
because air will frequently leak in around the hole caused by the needle. This will result in
inaccurate high readings. This is prevented by first inserting a foam seal pad onto the package
surface and piercing the needle through the foam.
CAUTION: If using alkaline batteries, do not plug the charger into the unit. These batteries
can overheat or crack if an extrnal voltage is applied and can melt the battery compartment.
The unit is fuse protected to prevent this. If the unit will not operate under battery power
alone but does operate with the charger plugged in , the fuse is probably blown.
CALIBRATION SETTING
Accurate SPAN calibration of the unit can be checked at any time by sampling room air,
which should give a reading of 20.9% oxygen, plus or minus 0.4%. If the reading is off, it can
be set by adjusting the SPAN potentiometer, located on the side of the unit, with the adjusting
tool supplied with the unit.
ZERO SETTING
The zero setting of the O2 channel is very stable, and will change little even over a period of
several months. Although usually not required, The O2 ZERO reading can be checked by
filling a plastic bag with nitrogen and then drawing out a sample as described previously.
Flush the bag thoroughly first because it is difficult to expell all the air out of it to get a true
zero sample. The zero will read 0.0, plus or minus 0.1% O2. If the reading is not in this range
adjust the O2 ZERO potentiometer as needed. Several turns will be needed to see any
movement in the reading, as the adjustment is not very sensitive.This adjustment should be
done carefully because it will affect all readings, and it must be done with N2 in the sensor.
Coffee Laboratory 589 Rappahannock Drive White Stone Va 22578 TEL (804) 435-5522
www.coffeelabequipment.com
