866.4.Maxtec www.maxtecinc.com
2
7
and
Keys-
The up and down arrow keys are used in
conjunction with the CALIBRATE key to calibrate the device.
C
Sample Inlet Connection
1.3 MAX-250 Oxygen Sensor
MAX-250 oxygen sensors offer quick response, stability and extra life on
the order of 1,500,000 percent hours.
The MAX-250 is a galvanic, partial pressure sensor that is specific
to oxygen. It consists of two electrodes (a cathode and an anode),
a teflon membrane and an electrolyte. Oxygen diffuses through the
teflon membrane and immediately reacts electrochemically at a gold
cathode. Concurrently, oxidation occurs electrochemically at a lead
anode, generating an electrical current and providing a voltage output.
Electrodes are immersed in a unique gelled weak acid electrolyte
which is responsible for the sensors long life and motion insensitive
characteristic. Since the sensor is specific to oxygen, the current
generated is proportional to the amount of oxygen present in the sample
gas. When no oxygen is present, there is no electrochemical reaction
and therefore, negligible current is produced. In this sense, the sensor is
self-zeroing.
CAUTION: The Maxtec MAX-250 oxygen sensor is a sealed device
containing a mild acid electrolyte, lead (Pb), and lead acetate. Lead
and lead acetate are hazardous waste constituents and should be
disposed of properly, or returned to Maxtec for proper disposal or
recovery.
CAUTION: Do not use ethylene oxide for sterilization. Do not
immerse the sensor in any cleaning solution, autoclave or expose
the sensor to high temperatures.
CAUTION: Dropping or severely jarring the sensor after calibration
may shift the calibration point enough to require recalibration.
2.0 SET-UP PROCEDURE
2.1 Battery Installation
All MAXO
2
®
analyzer units are powered by two, AA alkaline batteries (2
x 1.5 Volts) and are shipped without the batteries installed. The battery
compartment is accessible from the back side of the unit. To install the
batteries:
1. With the thumb, press down on the center of the battery compartment
cover and slide the cover off of the instrument case.
2. Install the two, AA, alkaline batteries (2 x 1.5 Volts) in the unit, observing
the orientation shown on the label inside the compartment.