Using The Dry Check Standard - Emerson Clarity II Instruction Manual

MODEL CLARITY II
6.6 USING THE DRY CHECK CUP
A dry check cup is available for checking the operation of the Clarity II turbidimeter. To use the dry check...
1. Calibrate the turbidimeter using one of the methods described in Section 6.2, 6.3, or 6.4. For regulatory report-
ing purposes, the turbidimeter must be calibrated against user-prepared formazin standard or against a com-
mercial standard acceptable to the regulatory agency.
2. After the calibration is complete, remove the sensor from the calibration solution, rinse it with water, and dry
thoroughly with a soft cloth.
3. Place the sensor in the dry check cup. Line up the pin on the check cup with the hole in the sensor and firm-
ly seat the sensor in the cup. Record the turbidity reading.
Different sensors in the same dry check will give slightly different readings.
Similarly, a single sensor tested in different dry checks will give slightly different
readings. If you are using different sensors and different dry checks, be sure to
keep track of which sensor was tested in which dry standard.
4. Periodically, check the operation by putting the sensor — be sure it is completely dry — in the dry check cup.
If the reading is acceptably close to the value when the sensor was last calibrated, the sensor does not need
recalibration. If the reading has drifted too far from the calibration value, recalibrate the sensor using formazin
or an acceptable alternative standard.
Do not use the dry check for recalibrating the sensor. The dry check is intended
ONLY for checking the operation of the loop.
5. After recalibrating the sensor, record the new turbidity reading in the dry check.
6. Keep the dry check covered and stored in a safe place when not in use.
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NOTE
NOTE
SECTION 6.0
CALIBRATION