Quantek 901 User manual

MODEL 901
OPERATING INSTRUCTIONS
Quantek Instruments
183 Magill Drive
Grafton, MA 01519
www.quantekinstruments.com
[phone]
2022

BEFORE YOU BEGIN
Thank you for your purchase. Before you
begin using the Model 901, please review the
following tips and precautions. 90% of repairs
are due to the issues outlined below:
Use a filter on the tip of the sample probe.
This prevents liquid intake.
Do not charge (or plug in) the instrument if
you install alkaline batteries.The charger
cannot tell the difference between
rechargeable and alkaline batteries. The
alkaline batteries will melt and/or explode if you
attempt to charge them!
The 901 is designed to be charged overnight,
and then unplugged during use.
Turn it off at the end of the day and plug it
in. If you leave it on, and plugged in, the
charger will stop after four hours, and the
analyzer batteries will deplete.
This is a frequent issue when operators leave it
on, and plugged into the charger, on a Friday.
When they come back Monday the analyzer is
dead and needs to be recharged.
Store the unit in a clean, dry location at the
end of the day/shift. Cleaning chemicals
commonly used in food production facilities can
corrode the circuitry in the unit.

GENERAL DESCRIPTION
The Quantek Model 901 is a battery-operated,
portable oxygen analyzer used for the
measurement of oxygen in packages, gas
streams, containers, and hundreds of other
applications.
INITIAL SETUP
The analyzer arrives with fully charged
batteries. Perform this procedure to
compensate for changes in elevation,
temperature, and/or humidity:
1) Turn the instrument on.
2) Remove the needle cover (or sheath).
3) Press the pump button –the reading will
go down temporarily.
4) Once the reading stabilizes, adjust the
span so that the reading is 20.9%.
It is recommended that you perform this
procedure at the beginning of each day. The
amount of oxygen in a room is always 20.9%,
regardless of ventilation or number of people
breathing nearby.
While humidity has a very small effect on O2
concentration, this effect is very minimal. At
100% relative humidity, the O2concentration in
air is about 20.4%.

Changes in elevation will also affect your initial
O2 reading. If the analyzer is calibrated for
sea level, and you bring it to 5000 feet above
sea level, you may notice the starting O2
concentration shows 17.9%. This is normal –
repeat the “initial setup” procedure so that the
instrument reads 20.9%.
UNDERSTANDING THE ADJUSTMENTS
The operating controls and adjustments
include power switch, pump switch, span, zero
and pump time adjustments:
SPAN: Use this on the side of the instrument
to adjust the analyzer to 20.9%. Press the
pump button, let the reading stabilize, then
adjust to 20.9%. You should do this once a
week, or if the instrument’s altitude has
changed. You should wait until the pump has
stopped, and the reading has stabilized, before
adjusting the span.
ZERO: This should generally not be touched.
See the section on checking the zero.
PUMP TIME: Use this to set the pump time. 5
seconds is ideal, but if your application,
package, or container has limited headspace,
you can set it to 3 seconds. Use a longer
pump time if the sensor is responding slow.

If you ever need to run the pump for longer
than 12 seconds, you can hold the button
down. This is rare, and would only be
applicable to situations where you might not
have the probe positioned properly to get a
good reading.
When turning the PUMP TIME adjustment:
COUNTERCLOCKWISE = SHORTER
CLOCKWISE = LONGER
PRECAUTIONS
Follow these other guidelines to prevent
damage:
1. Do not immerse in water or spray water
on the unit.
2. Do not drop the unit.
3. Store the unit in a clean, dry location at
the end of the day/shift. Cleaning
chemicals commonly used in food

production facilities can corrode the
circuitry in the unit.
4. Do not operate the unit while plugged in
–it is designed to be operated from the
batteries.
5. Be sure to check the battery polarity (+
and -) if you decide to swap out
batteries.
RECHARGING ANALYZER
To charge the analyzer, shut it off and leave it
plugged in to the charger. If you need to use it
right away, you can substitute alkaline AA
batteries, but again –DO NOT CHARGE THE
UNIT WITH ALKALINES INSTALLED!
The charger will go from solid orange, to
blinking orange, to fast blinking green, to slow
blinking green, to solid green. Your charger
may look different.

Note: These batteries are NiMH 2600 mAh
AAs. The total time to charge the analyzer fully
from 0-100% charge is approximately 2-3
hours.
The rechargeable batteries are high quality,
low self-discharge batteries. If you do need to
replace them, any rechargeable NiMH or
NiCad batteries can be used. Mixing brands is
not advised.
IF YOUR CHARGER IS DAMAGED:
Contact us for a replacement charger. In the
meantime, use alkalines.
If you absolutely must purchase a charger
locally, the specifications are: 2.5mm barrel,
center +. Most NiMH chargers will work, just
be sure to use a charger that is designed for 4
AA NiMH cells. Most NiMH chargers will work
for a range of AA quantities (i.e. 2-10 cells).
Please note: you will void your warranty if you
use a non-Quantek charger.
OPERATION SUMMARY:
1. Insert a particulate filter onto the end of the
sample probe. If you are testing through a
septum, or a package, you’ll want to use a
needle at the end of the probe. If you are

testing a gas stream, or a chamber, you may
want to use a blunt needle.
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 2 to 12 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
(after the pump has stopped) for the reading to
stabilize. Room air should give a reading of
20.5 to 21.3 % oxygen. Adjust the oxygen
span to 20.9% if you’d like.
NOTE: You only need to perform step three
once a day –at most.
4. For non package applications –place the
probe in the area you’d like to measure.
Depress the PUMP switch and wait for the
reading to stabilize (12-18 seconds). Leave the
needle in the gas stream until a stable reading
has been obtained.
NOTE: Make sure that you have the blunt tip
needle placed in a location where ambient air
cannot be drawn into the probe.

To see examples of package testing, use the
following URL:
www.quantekinstruments.com/901support/
CALIBRATION OVERVIEW
The factory calibration schedule is two years
after initial purchase, and every year thereafter.
Customers who are comfortable self-calibrating
can use the procedure below.
Since the response of the oxygen sensor is
very linear (especially between 0.0% and
20.9%), checking the zero point and the span
point are sufficient for excellent accuracy.
Factory calibration includes a full checkup of all
components (such as the pump, sample probe,
circuit board, etc) and leak test of the system.
SELF-CALIBRATION: O2 SPAN
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 0.3%. If the reading is off, it can
be set by adjusting the SPAN potentiometer,
located on the side of the unit, with the flathead
screwdriver supplied.
Significant changes in elevation will require
resetting the span calibration –for example, if

you take the instrument from sea level to
Denver, it will read 17.9%.
The amount of oxygen in a room will not vary
much –even in a closed building with many
people. However, if you ever want to be sure,
you can set the span using outside fresh air.
SELF-CALIBRATION: O2 ZERO
The zero setting of the O2channel is very
stable, and will change little even over a period
of several months. Although usually not
required, The O2ZERO reading can be
checked one of two ways:
1) BEST METHOD –
We also now include an orange tube for
calibration which you can insert into a tube of
flowing gas:
Also, make sure that the nitrogen has been
flowing for at least 30 seconds to flush out any
other air that may have been in the tubing.