Campbell Scientific CS511 Dissolved Oxygen Probe - Manual (Page 14)

CS511-L Dissolved Oxygen Probe
4.3 Mount Probe
Mount the CS511 in water at a slight angle, which prevents bubbles from
becoming trapped on the membrane.
5. Overview
The CS511 is a galvanic probe which produces a millivolt signal proportional
to the amount of oxygen present in the measured medium. Oxygen diffuses
through the membrane onto the cathode, reacts chemically, and combines with
the anode. An electrical current is produced by this chemical reaction which is
converted from microamps to millivolts by an in-line resistor. An in-line
thermistor also conditions the signal providing automatic temperature
compensation. With these features, the probe produces a linear, millivolt
output proportional to the oxygen present in the medium in which it is placed.
The probe consists of two parts, an upper part with cathode, anode, and cable,
and a lower part comprising of a screw-on membrane cap. The probe is
shipped dry, but has a membrane installed in the cap. With the membrane in
place, the cap must be filled with electrolyte solution before the cap is screwed
onto the top component.
The probe is self-polarizing and requires no external power source.
The probe's robust construction and simple design make maintenance and
servicing it straightforward. There is no need to send the probe back to the
factory for servicing. It uses a strong, easy-to-clean, and easy-to-change
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