Hanna Instruments HI 9023C, Инструкция по эксплуатации

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• Once the electrode is submerged in the
buffer solution, the LCD will notify the user
if the reading is not stable by an intermit-
tent "NOT READY". Only when the reading
is stable, will it change to a blinking
"READY" and "CON".
• Press the CFM key to confirm the calibra-
tion. If the reading is not close to the
selected buffer, "WRONG
1
BUF
" and
"WRONG " will blink alternatively. If the
reading is close to the selected buffer, the
meter stores the reading (and adjusts the
offset point). The buffer value is then dis-
played on the primary LCD and the
secondary LCD will display another buffer
value (e.g."4.01").
• Press the CAL key and the calibration pro-
cess is ended with only the offset of the
meter calibrated. For best accuracy how-
ever, do not press CAL and proceed with a
two-point calibration.
TWO-POINT CALIBRATION
After calibrating at 6.86 or 7.01 pH (see above), for the second buffer
use pH 4.01 if you are going to measure acidic samples, and pH 9.18
or pH 10.01 if you are measuring alkaline solutions.
• Proceed as described in “One-point cali-
bration above but do not end the calibration
by pressing CAL.
• After the first calibration point is confirmed,
immerse the pH electrode into the second
buffer solution (pH 4.01, 9.18 or 10.01)
and stir gently.
Note: The electrode should be submerged
approximately 4 cm (1½") into the
solution with the temperature probe lo-
cated as close to it as possible.
• Select the second buffer value on the sec-
ondary display by pressing the
Ï
°C or
Ð
°C °C
°C °C
°C key.
CAL
1
BUF
pH
pH
WRONG
WRONG 1
BUF
CFM
CAL
NOT READY
READY
CON
4 cm
(1½")
HI 7004
°C
°C
or
21
• When the “READY” and “CON” symbols
blink on the display, the reading is stable
and the calibration can be confirmed.
• Press the CFM key. If the reading is not close to the selected
buffer solution, “WRONG
2
BUF
” and “WRONG ” will blink alter-
natively. If the reading is close to the selected buffer, the slope
and the offset are calibrated. The values will be stored in memory
and the meter will return to the operating mode.
Note: The meter will automatically skip the buffer that was used for
the first calibration to avoid erroneous calibration. At least 1
full pH unit is required between the two buffers used for the
offset and slope calibration. As a result, once calibrated at
either pH 6.86 or 7.01, the microprocessor will automatically
ignore the other one for the second point calibration. It will do
likewise for pH 9.18 and 10.01
Note: During calibration, the secondary LCD displays the selected
buffer value. With HI 9025C, press the RANGE key to display
the buffer temperature during calibration.
PROCEDURE FOR HI 9110, HI 9210 & HI 9210N:
Manual Temperature Compensation
Note:
The pH/°C electrode of HI 9210N incorporates a temperature
sensor which performs automatic temperature compensation.
Consequently, the following 5 paragraphs are irrelevant to
HI 9210N and you can just proceed with pH calibration below.
• Press pH/°C SET key for HI 9110 or the RANGE key for HI 9210 to
select the manual temperature setting. The "°C" symbol will be
displayed to indicate the temperature setting mode.
• Remove the protective cap on the top of the meter to have access
to the calibration trimmers.
• Record the temperature of the buffer with a Checktemp C or an
READY
CON
WRONG
WRONG
2
BUF
CFM
pH
°C
SET
RANGE
°C