Campbell Scientific CSIM11 pH and ORP Sensors - Manual (Page 17)

CSIM11 pH and ORP Probes
Drift: < 2 mV per week
Power: Two 3 Vdc lithium batteries that should last the
lifetime of the sensor
Length: 17.8 cm (7.0 in)
Diameter: 3.0 cm (1.2 in)
Weight with 15 ft cable: 0.5 kg (1 lb)
6.1.1 pH Sensor
pH Range: 0 to 14
Zero Potential: 7.0 pH ±0.2 pH
Sodium Error: < 0.05 pH in 0.1 Molar Na+ ion at 12.8 pH
Output: ±59 mV/pH unit
6.1.2 ORP Sensor
ORP Range: –700 to +1100 mV
7. Installation
If you are programming your datalogger with Short Cut, skip Section 7.3,
Wiring, and Section 7.4, Datalogger Programming; Short Cut does this work
for you. See Section 4, Quickstart, for a Short Cut tutorial.
7.1 Preparation for Use
All electrodes are shipped with a wetting cap covering the measuring end. This
cap contains a solution of pH 4 buffer saturated with potassium chloride (KCl).
Remove the wetting cap before calibration. There may be some dry KCl
crystals forming on the outside of the cap. These deposits are expected over
time and can be wiped or rinsed off. Save the cap for future long-term storage.
Rinse the electrode with distilled water and it is ready for use.
Do not store the sensor in distilled water, as the gel layer will become depleted.
If this happens, the gel layer can often be rehydrated by soaking the sensor in
the pH 4 buffer solution overnight.
7.2 Orientation
The CSIM11/CSIM11-ORP can be installed without regard to orientation.
Unlike other pH/ORP sensors, the problem with air bubbles adversely affecting
the measurement has been eliminated by Wedgewood Analytical’s use of a
gelled reference solution and a patented plunger technology.
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