Manual

XII. ACCESSORIES
A. pH Buffer Solutions
pH buffers are available in pH values of 4, 7 and 10. Myron L Company
buffer solutions are traceable to NIST certified pH references and are
color-coded for instant identification. They are also mold inhibited and
accurate to within ±0.01 pH units @ 25°C. Order 4, 7 or 10 Buffer.
B. pH Sensor Storage Solution
Myron L Storage Solution prolongs the life of the pH sensor. It is available
in quarts and gallons. Order SSQ or SSG.
C. Soft Protective Case
Padded Cordura® Nylon carrying case features a belt clip for hands-free
mobility. Model: UCC
® Registered trade mark of DuPont
D. Replacement pH/ORP Sensor
Model RPR is gel filled and features a unique porous liquid junction. It is
user-replaceable and comes with easy to follow instructions.
E. Data Port
There is a 4 pin connector marked “Factory Use Only” on the bottom of
the Ultrameter. It is used to interrogate the instrument during final
inspection. Applications in the future for downloading recorded data are
being considered, but not implemented, as of this printing.
F. Conductivity/TDS Standard Solutions
For your other Myron L instruments, our NIST standard solutions are
available in a variety of salts and concentrations to fit your needs. Call or
write for information.
XIII. pH and ORP MEASURING
A. pH
1. pH as an Indicator
pH is the measurement of Acidity or Alkalinity of an aqueous solution. It is
also stated as the Hydrogen Ion activity of a solution. pH measures the
effective, not the total, acidity of a solution.
A 4% solution of acetic acid (pH 4, vinegar) - can be quite palatable, but a
4% solution of sulfuric acid (pH 0), is a violent poison. pH provides the
needed quantitative information by expressing the degree of activity
of
an acid or base.
19
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XI. TROUBLESHOOTING CHART
18
Clean and rejuvenate sensor (ref. Cleaning pH/ORP Sensor, pg. 16) and recalibrate. If no improvement, replace pH/ORP sensor (ref. pH/ORP Sensor Replacement, pg. 16).
Symptom Possible Cause Corrective Action No display, even though measurement key pressed
Battery weak or not connected. Check connections or replace battery.
(ref. Battery Replacement, pg. 16)
Inaccurate pH readings 1. pH calibration needed. (ref. pH Cal. pg. 10)
2. Cross-contamination from residual pH buffers or samples in sensor well. 3. Calibration with expired pH buffers.
1. Recalibrate instrument 2. Thoroughly rinse sensor well. 3. Recalibrate using fresh buffers (ref. pH Buffer Solutions, pg. 19).
No response to pH changes Sensor bulb is cracked or an
electromechanical short caused by an internal crack.
Replace pH/ORP sensor (ref. pH/ORP Sensor Replacement pg. 16).
Will not adjust down to pH 7 pH/ORP sensor has lost KCl.
Clean and rejuvenate sensor (ref. Cleaning pH/ORP Sensor, pg. 16) and recalibrate. If no improvement, replace pH/ORP sensor (ref. pH/ORP Sensor Replacement, pg. 16).
pH readings drift or respond slowly to changes in buffers/samples or “FAC” is displayed repeatedly
1. Temporary condition due to “memory” of solution in pH sensor well for long periods. 2. Bulb dirty or dried out. 3. Reference junction clogged or coated.