GENERAL OPERATION
•
The meter is supplied
complete with a 9V bat-
tery. Remove the battery
compartment cover on
the back of the meter and
install the battery while
paying attention to its po-
larity.
•
Connect the MA923D/1
probe to the meter.
•
Turn the instrument 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 mea-
surement.
•
Always remove the electrode protective cap
before taking any measurement. If the elec-
trode has been left dry, soak the tip (bottom
2.5 cm) in M10000 rinse solution for a few
minutes.
•
The temperature reading can be displayed
in °C or °F unit; to select the desired scale,
press and hold the “ON/OFF” key until “TEMP”
and the current temperature unit are dis-
played on the secondary LCD. Use the “SET”
button to select the unit and then press the
“ON/OFF” key 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 dis-
play and the “HOLD”
message appear on
the secondary LCD.
•
After measurements, switch the meter off
by pressing the “ON/OFF” key. The “OFF”
message appears on the LCD; release the
button.
•
After use, replace the electrode protective
cap with a few drops of storage solution.
TAKING pH MEASUREMENTS
•
Select the “pH” mode with the “SET ” key.
•
Immerse the tip (2.5 cm) of the probe in the
sample and stir gently.
•
Read the pH value when the clock symbol
stops blinking.
Note: 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).
pH CALIBRATION PROCEDURE
It is recommended to recalibrate the meter at
least once every three weeks.
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:
•
Select the “pH” mode with the “SET ” key.
•
Select the 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 de-
sired buffer set with the “SET” key: “7.01
USER MANUAL
MI 106
pH/mV/Temperature
Portable Meter
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 the
“ON/OFF” key again to exit.
•
Remove the protective cap, then immerse
the probe in the first buffer (pH 7.01 or
6.86).
•
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.
•
The meter automatically recognizes the buffer
value: if a valid buffer is detected, then its
value is displayed on the LCD
together with the “REC” mes-
sage, and the first calibra-
tion point is accepted.
•
The meter will then require
the second buffer by show-
ing the “pH 4.01 USE” mes-
sage.
Immerse the probe in the second buffer
solution (pH 4.01 or 10.01 or 9.18). If a valid
buffer is recognized, the meter completes
the calibration procedure, shows the “OK 2”
message for a few seconds, then returns
to the normal mode.
ISTMI106R1 06/04
