900719_FOCE : SBE18 pH Sensor This page last changed on May 21, 2008 by chadillac. # General Description The SBE 18 pH Sensor uses a pressure-balanced glass-electrode / Ag/AgCl-reference pH probe to provide in-situ measurements at depths up to 1200 meters (3900 ft). 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 and associated interface electronics 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 and 19plus SEACAT, and SBE 25 SEALOGGER). Power / signal interface cables and mounting hardware are available separately. The SBE 18's interface circuits buffer and offset the differential glass- electrode/reference potential to produce a high-level, pH-dependant, output voltage. Computation of pH in engineering units is typically done using our SEASOFT© software. Sea-Bird calibrates the pH sensor against precision buffer solutions (4, 7, and 10 pH ± 0.02 pH). These calibration results are tabulated on a certificate furnished with each sensor. # Links Datasheet User's Manual Sensor Calibration App Note Sensor Storage, Mainentance, and Calibration App Note Sensor Hookups App Note Sensor Calibration Equation Error App Note Desiccant Usage App Note Moored Applications App Note SeaBird Home Page Attachments: 18photo.jpg (image/pjpeg) 18photo.jpg (image/pjpeg) 18photo.jpg (image/pjpeg)

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