User's Manual

FUNCTIONAL DESCRIPTION PROBE
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1. D.O. Probe
2. Protective Cap
3. Watertight Shielded
Cable
4. Polypropylene Probe
Body
5. Temperature Sensor
6. O-Ring Seal
7. Silver Chloride Anode
(sensor element)
8. Platinum Cathode
(sensor element)
9. Oxygen Permeable
PTFE Membrane
10.Protective Cap
salty waters and the altitude compensation
readjusts for the altitude variance (HI 9143 only).
Four 1.5V AA alkaline batteries provide power
and make the instrument completely portable.
HI 9143 and HI 9145 are also designed to be
used with a battery recharger or a 12VDC
power supply. A 12VDC input jack is
incorporated into the housing.
A microprocessor ensures an accurate and
rapid calibration and measurement. The case
rugged and water-resistant for maximum
protection in the field as well as in the laboratory.
The dissolved oxygen probe has a membrane
covering the polarographic sensor elements
and a built-in thermistor for temperature
measurement and compensation. The thin
permeable membrane isolates the sensor
elements from the testing solution, but allows
oxygen to enter. When a voltage is applied
across the sensor, oxygen that passes through
the membrane causes a current to flow from
which the oxygen concentration is determined.
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