User Manual
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Calibration is purposely limited in the Po o l Pr o to
±
10% for the
conductivity cell because more than that indicates damage, not drift.
Likewise, calibration changes are limited to
±
1 pH unit because more than
that indicates the end of the sensor’s lifetime, and it should be replaced.
C. Conductivity, MIN/SALT, TDS Practices to Maintain Calibration
1. Clean oily lms or organic material from the cell electrodes
with foaming cleaner or mild acid. Do not scrub inside the cell.
2. Calibrate with solutions close to the measurements you make.
Readings are compensated for temperature based on the type
of solution. If you choose to measure tap water with a KCl
compensation, which is often done (ref. An Example, pg. 38), and
you calibrate with 442 solution because it is handy,
the further away from 25°C you are, the more error you
have. Your records of calibration changes will reect
temperature changes more than the instrument’s accuracy.
3. Rinse out the cell with pure water after taking measurements.
Allowing slow dissolving crystals to form in the cell
contaminates future samples.
4. For maximum accuracy, keep the pH sensor cap on tight so
that no uid washes into the conductivity cell.
D. pH and ORP Practices to Maintain Calibration
1. Keep the sensor wet with Myron L Storage Solution.
2. Rinse away caustic solutions immediately after use.
ORP calibration solutions are caustic, and
±
5% is considered very
accurate. By using the pH zero setting (0 mV = 7 pH) for ORP and
precision electronics for detection, the Po o l Pr o delivers better accuracy
without calibration than a simpler instrument could using calibration
solutions.
IX. MEMORY
This feature allows up to 100 readings with their temperatures to be
stored simultaneously for later recall. At the same time, the TIME and
DATE are also recorded. To download the memory to a computer, (ref.
bluDock™ Wireless Data Transfer Instructions, pg. 29).