Myron L 3P - Manual (Page 11)

XII. A C C E S S O R I E S
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
:
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 buf
fers or samples in sensor well.
3. Calibration with expired pH buf
fers.
1. Recalibrate instrument 2.
Thoroughly rinse sensor well. 3. Recalibrate using fresh buf
fers
(ref. pH Buf
fer 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 buf
fers/samples or
“F
AC
” is
displayed repeatedly
1.
T
emporary 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.