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The Kemtrak DCP007 photometer measures at two wavelengths. A primary "absorbing" wavelength is used to measure the substance being monitored while a "non absorbing" reference wavelength is used to compensate for turbidity, air bubbles and/or fouling.

Fiber optics are used to shine a precisely focused light beam through the process medium and back to a silicon photo-detector. A second photo-detector is used directly on the lamps to compensate for temperature effects and aging. The resulting measurements are very accurate with low drift and long-term calibration stability.
The attenuation of the transmitted light beam caused by light absorbing substances in the process medium is mathematically described by the Beer-Lambert law. |
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Applying the Beer-Lambert law (below), the concentration of the sample can be calculated. |
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A = ε l c |
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where: |
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A |
= |
absorbance (= - log transmittance) |
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ε |
= |
molar absorptivity coefficient |
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l |
= |
optical path length |
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c |
= |
concentration of absorbing species |
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The Kemtrak DCP007 photometer is ideally suited for industrial environments where simplicity, stability and low maintenance is vital. |