Conductivity isoPodTM - eDAQ - #1

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WARRANTY: eDAQ hardware units are supported by a three year warranty www.eDAQ.com E-mail: info@edaq.com e-corder® is a registered trademark and isoPod™ a trademark of eDAQ Pty Ltd. All other trademarks are the property of their respective owners. PT5/09 Conductivity isoPod™ (Model EP357) Document Number: M-EP357-0709 Copyright © eDAQ 2009 • Software controlled • Plug and play installation • Electrical isolation minimizes noise and crosstalk • 12 input ranges, from 2 ìS to 200 mS Description An electrically isolated, compact signal conditioner for use with ecorder units, for continuous monitoring of solution conductance. Compatibility This isoPod be used with most types of two-electrode conductivity cells, including: • ET915 Dip-In Conductivity Electrode • ET908 Flow-Thru Conductivity Electrode (for 1/8" OD tubing) • ET916 Flow-Thru Conductivity Electrode (for 1/16" OD tubing) Use with Chart software version 5.5.6, or later, on Windows XP or later computers. Applications Studies where continuous monitoring of solution electrical conductance/ resistance is required – e.g. ion chromatography, flow injection analysis, or conductiometric titrations. Theory of Operation The Conductivity isoPod measures the alternating current (AC) across a suitable conductivity cell by applying a square bipolar potential pulse across the pair electrodes that comprise the cell. A DC analog voltage signal, proportional to the conductance, is output. The isoPod automatically sets excitation amplitude and frequency to an optimal value for a given gain range. Calibration The specific conductivity of a solution is obtained by calibrating the conductivity cell. First measure the conductance of a solution of known value (e.g. 0.1 mol/L KCl) then use the Units Conversion feature of the Chart software to equate this signal to the known specific conductivity. Output signal: 0 – 2 V Low-pass filter: 1, 2, 5, 10, 20, 50, 100 Hz Noise: 250 V rms AC waveform amplitude: 20 or 200 mV p-p AC waveform shape: Square pulse AC waveform frequency: 0.5, 1.0 or 10 kHz Common mode rejection: > 120 dB Specifications