USER MANUAL
MI 806
pH/EC/TDS/Temperature
Portable Meter
GENERAL OPERATION
• The meter is supplied
complete with a 9V battery.
Remove the battery cover
on the back of the meter
and install the battery while
paying attention to its
polarity.
• Connect the
MA851D/1
probe to the meter and turn
it on by pressing the
ON/OFF key.
• At start-up, the LCD shows the
percentage of the remaining battery life
for a few seconds, and then the current
measurement.
• To select the temperature
measurement unit (°C or °F), press and
hold the “ON/OFF” key until “TEMP” and
the current temperature unit are
displayed on the secondary LCD. Use
the “SET” button to select the unit, then
press “ON/OFF” a couple of times to
return to normal mode.
• To activate the HOLD
function, keep pressed
the “HOLD” key. The
measured value will be
frozen on the display
and the “HOLD”
message appears on
the secondary LCD.
• To set the measurement range (pH,
μS, ppm), press the “RANGE” key. The
chosen mode will be stored until next
change.
• Before taking any measurement, make
sure that the meter has been calibrated
(the “CAL” tag is displayed on the left
lower corner of the LCD).
• After measurements, switch the meter
off by pressing the “ON/OFF” key. The
“OFF” message appears on the LCD;
release the button.
• Store the electrode with a few drops of
storage solution in the protective cap.
TAKING pH MEASUREMENTS
• Always remove the electrode
protective cap before taking any
measurement. If the electrode has been
left dry, soak the tip (bottom 2.5 cm) in
M10000
rinse solution for a few minutes
to reactivate it.
• Select the pH range with the “RANGE”
key.
• Immerse the tip (2.5 cm) of the probe
into the sample and stir gently.
• Read the pH value when the clock
symbol stops blinking.
pH CALIBRATION PROCEDURE
A) Preparation, Buffer solutions:
1.
pH 7.01
/
6.86 (MA9007 / MA9006)
2.
pH 4.01
(
MA9004
) for acidic
calibration (pH < 7) or
pH 10.01 / 9.18
(
MA9010 / MA9009
) for alkaline range
(pH > 7).
Use two beakers for each buffer
solution: one beaker for rinsing the
probe, the other for calibration. In this
way the cross contamination between
solutions is minimized.
B) Procedure:
• Enter the pH mode with the “RANGE”
key.
Select calibration buffer set: press and
hold the “ON/OFF” key until the LCD
shows “TEMP”.
Press again this key and the “BUFF”
message will appear; then select the
desired buffer set with the “SET” key:
“7.01 pH BUFF” (for standard solutions:
pH 4.01, 7.01, 10.01) or “6.86 pH BUFF”
(for NIST solutions: pH 4.01, 6.86, 9.18).
Press “ON/OFF” again to exit.
• Remove the protective cap, then
immerse the probe in the first buffer
solution.
• Press and hold the
“ON/OFF” key until
“CAL” is displayed on
the lower LCD. Release
the button and the
message “7.01 pH USE”
(or “6.86 pH USE” for
NIST buffer set) will be
displayed.
• For a single point pH calibration, place
the probe in any buffer from the selected
set (e.g. pH 4.01 or 7.01/6.86 or
10.01/9.18). The meter will automatically
recognize the buffer value, store the
calibration point and return to normal
mode.
• If using pH 7.01 (or pH 6.86), after
recognition of the buffer press the
“ON/OFF” button to return to normal
mode.
• For a two point pH calibration, place
the probe in pH 7.01 buffer (or pH 6.86,
if the NIST buffer set was selected).
The meter will recognize
the buffer value and
then display pH 4.01
USE.
• Place the probe in the second buffer
(pH 4.01 or 10.01, or, if using NIST, pH
4.01 or 9.18). When the second buffer is
recognized, the LCD will display “OK” for
1 second and the meter will return to
normal mode.
• The “CAL” tag is displayed on the LCD
to indicate that the meter is calibrated.
