Model SBE 18 -pH Sensor

The SBE 18 pH Sensor uses a pressure-balanced glass-electrode /Ag/AgCl-reference pH probe to provide in-situ measurements at depths to 1200 meters. The replaceable pH probe is permanently sealed and is supplied with a soaker bottle attachment that prevents the reference electrode from drying out during storage. The sensor is a modular, self-contained package that is easy to install, service, and calibrate.

The SBE 18 is intended for use as an add-on auxiliary sensor for profiling CTDs (SBE 9plus; SBE 19, 19plus, and 19plus V2 SeaCAT; and SBE 25 and 25plus Sealogger). Power / signal interface cables and mounting hardware are available separately.

FEATURES

• Voltage output; interface circuits buffer and offset the differential glass-electrode/reference potential to produce a high-level, pH-dependant, output voltage.
• Calibrated against precision buffer solutions (4, 7, and 10 pH ± 0.02 pH); results tabulated on a certificate furnished with each sensor.
• 1200 m housing.
• Supplied with plastic soaker bottle and KCl soaker solution.
• Seasoft© V2 Windows software package (computation of pH in engineering units).
• Five-year limited warranty.

OPTIONS

• Straight endcap for vertical mounting, or right angle endcap for horizontal mounting (for example, in an extension stand below an SBE 32 Carousel Water Sampler).
• XSG or wet-pluggable MCBH connector.

Specifications

Performance

Measurement Range: 0 to 14 pH
Initial Accuracy: ± 0.1 pH (stated accuracy achievable with frequent field calibrations)
Time Response: 1 sec (time to reach 63% of final value following a step change in pH)

Electrical

Input Power: 6 - 24 VDC, 15 mA
Output Signal: 0 to +5 V

Mechanical

Housing, Depth rating, & Weight: Anodized aluminum (6061-T6), stainless steel
1200 m depth rating
0.7 kg in air, 0.4 kg in water