Myron L T6/PH - Manual (Page 3)

TDS CALIBRATION
TDS STANDARD SOLUTIONS: A Standard Solution has a known
conductivity and ppm/TDS. Your meter was calibrated at the factory
using Standard Solutions. You can keep your meter accurate by
using these same Standard Solutions. 442 Standard Solutions
approximate the conductivity characteristics of most natural waters.
To pick the right Standard Solution for your meter see
ACCESSORIES.
How often you calibrate your meter depends on how much you
use it. For once a day use, recalibrate it every three months.
CHECKING TDS CALIBRATION
1. Turn Range Switch to the x1000 range (T2/pH only).
2. Test a sample of appropriate Standard Solution.
CAUTION: Throw away the Standard Solution as you use it. Don't
put the used samples back in the bottle.
3. If the pDS Meter does not indicate the same value as is on the
Standard Solution bottle's label, first clean the cell. For directions
on how to do this see CELL CUP inside. Rinse the cell thoroughly
and test the Standard Solution again. If the pDS Meter still does
not indicate the correct value, recalibrate it as described below.
TO RECALIBRATE TDS
1. Remove the bottom cover using fingernails or a small screwdriver
to loosen the front or rear edge. Identify the TDS Calibration
Control(s) so you can find them by touch while calibrating (Model
T2/pH has three; see photo below).
2. Test another sample of the Standard Solution (be careful to not
splash solution inside the meter).
3. Adjust the Master Calibration Control until the meter indicates
the value on the Standard Solution label.
NOTE: T2/pH and T6/pH Meters may be calibrated to read either
442 or NaCI parts per million, but not micromhos.
4. The Master Calibration Control on model T2/pH adjusts ail ranges.
For best accuracy in the lower ranges, get the recommended
Standard Solutions for the x100 and x10 ranges. Use the x100
and x10 trimmers to recalibrate those ranges as in steps 2 and 3
above.
5. Turn the Range Switch to "S" and press the black button (T2/
pH); or press the green button (T6/pH).
6. Compare the meter reading to the INTERNAL STANDARD value
on the meter's bottom label. If they are noticeably different, mark
the new value in place of the old one.
USING YOUR METER
TDS MEASUREMENT: Model T2/pH
1. Turn the Range Switch to the desired range. If you don't know
which range to use, set it to 1000.
2. Rinse the cell cup three times with the sample you want to test.
(For very hot or very cold samples see TEMPERATURE
COMPENSATION below.)
NEVER FILL CELL BY DIPPING METER INTO WATER!
3. Fill the cell with another sample to at least
1 /
4
" (6mm) above the
upper electrode.
4. Press the black button.
5. Read the dial's black scale value indicated by the pointer. If the
pointer is very low on the left or goes off the scale to the right, try
the next lower or higher range.
6. MuItiply the dial's black scale value by the range setting to
determine TDS in parts per million.
7. If the pointer goes off the scale to the right on the x1000 range,
try RANGE DOUBLING (see FIELD CALIBRATION) or use an
RE-10 range extender (see ACCESSORIES).
TDS MEASUREMENT: Model T6/pH
1. Rinse and fill the cell cup as in steps 2 and 3 above.
2. Press the black button.
3. Read the TDS value in parts per million indicated by the pointer
on the dial's black scale.
4. If the pointer goes off the scale to the right, try RANGE DOUBLING
(see FIELD CALIBRATION) or use an RE10 range extender (see
ACCESSORIES).
NOTE: When finished, RINSE THE CELL CUP with clean water,
preferably distilled or deionized.
pH MEASUREMENT
1. Obtain sample to be tested, if necessary, heat or cool it to between
50
°
and 160
°
F (10
°
-71
°
C).
2. Remove the pH compartment cap and sharply shake out any
liquid.
3. Pour or squirt the sample into the built-in cell cup, especially the
small pH compartment. Shake out and repeat three times with
the sample to be tested. These may be the same rinsings used
to condition the cell for the TDS measurement.
4. Press the red button. The pointer immediately indicates the
pH of the sample on the red scale. If the pointer drifts, wait
approximately 30 seconds and press the button again to obtain
a stable reading of pH. If drifting continues, the electrode may be
coated with a film. Use a liquid cleaner such as Windex
™ or
Fantastic ™ clean the pH sensor bulb (see pH SENSOR).
5. Rinse both pH and conductivity parts of the cell with clean water.
LEAVE SOME LlOUID IN AND RECAP THE pH
COMPARTMENT.
TEMPERATURE COMPENSATION: For very hot or very cold
solutions let the three rinse samples each remain in the cell for several
seconds, then immediately fill the cell with the sample you want to
test (step 3 above). This allows the automatic temperature
compensation feature time to work properly.
CAUTION:
ALWAYS store your pH sensor wet and with the cap on.
ALWAYS rinse the cell cup with pure water immediately
after use or cleaning. This will prevent the build-up of deposits and
possible contamination of the sample.
DO NOT test solutions which could damage the pH sensor. See
MAINTENANCE.
DO NOT use with samples hotter than 160
°
F (71
°
C). The readings
WILL NOT be accurate.
DO NOT splash solvents such as lacquer thinner, acetone, benzene
or chlorinated solvents on the plastic case.
DO NOT fix or modify the meter. That will void your warranty. See
SERVICE for details or consult Myron L
DO NOT DIP THE INSTRUMENT INTO WATER. If water does get
inside the instrument, see MAINTENANCE for instructions on drying
it.
NOTE: The feature described below is intended as a quick field
calibration check, or for using the range doubling technique. It is not
a replacement for calibration with Standard Solution.
INTERNAL STANDARD: An INTERNAL STANDARD value for each
meter is on the label on the bottom cover of each meter. Use it
between normal calibrations as a field check of your meter's accuracy.
To verify your meter's calibration:
1. Turn the Range Switch to "S" and press the black button (T2/
pH); or press the green button (T6/pH).
2. If the reading matches the INTERNAL STANDARD value on the
bottom label, your meter is in calibration. If not, see TDS
CALIBRATION above.