15
14
5. Measurement
Measuring Ion Concentration
1.
Switch on meter. The ION 5 and ION 6 meters
will automatically enter the ion measurement
mode. No annunciator will appear.
See figure
2.
Prepare samples as necessary (i.e., add Ionic
Strength adjuster). Sample preparation varies
depending on ion type—see your electrode manual for details on the specific
electrode that you are using.
3.
Dip electrode into the sample. The sensor or glass bulb of the electrode must be
completely immersed into the sample. For best results, use a magnetic stirrer to
ensure a homogenous sample.
4.
Wait for reading to stabilize. Note reading.
ION TIP:
Concentration readings are not temperature compensated. Try to avoid
temperature fluctuations in your standards and samples.
Measuring mV
The mV mode is provided to allow you to check performance and calibration of
your ion selective electrode.
To verify electrode operation, check mV reading in calibration standards one decade
apart in value (i.e.: 1 ppm; 10 ppm). Use the MODE key to toggle between ion and
mV measurement (ION 6 meter MODE key switches between pH, temperature, ion
and mV).
Consult your electrode manual for expected mV (slope) value. If your actual mV
readings are not within expected values as stated in your electrode manual, you
may need to recondition or replace your electrode.
5.1
5.2
A
A
Measuring pH and temperature (ION 6 meter only)
The Acorn ION 6 meter also takes readings in
pH and temperature.
1.
Rinse both electrode and temperature sensor
with distilled water.
2.
Turn meter on. ION 6 meter automatically
enters ion measurement mode. Press MODE
key until meter enters pH measurement mode.
pH annunciator will appear in the upper right
corner of the LCD.
See figure
3.
Dip electrode and temperature sensor
approximately 1" to 2" into sample.
Stir gently and wait for display to stabilize.
Note pH reading.
4.
Press MODE key to see your temperature
reading. °C annunciator will appear in the lower right corner of the LCD.
See figure
Measuring pH with manual temperature compensation
When no temperature probe is connected, the meter will compensate based on a
manually entered temperature value. The factory default setting is 25°C (no temper-
ature compensation). You can compensate for temperature manually by entering the
temperature of your solution using the procedure below.
1.
Press the MODE key until ”°C” shows in the display to enter Temperature mode.
2.
Check the temperature of your solution using an NIST-certified thermometer or
other thermometer known to be accurate
3.
Press CAL key to enter temperature calibration mode. The display shows “CA”
momentarily and the displayed reading flashes. Use the
▲
and
▼
keys to match
the displayed value to the temperature of your solution.
4.
Press ENTER key.
5.
Press MODE key to return to pH measurement mode.
Hold function
To freeze your reading, press the HOLD key once.
The LCD show "HO" to indicate the HOLD func-
tion is activated. See figure
Press HOLD key again to deactivate the HOLD
function and return to measurement mode.
pH
A
C
B
HO
A
A
B
A
5.3
5.4
5.5
Содержание ION 5 Acorn Series
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