Instruction manual

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11
From pH measurement mode press CAL key to enter calibration mode as
described in section 4.2. The LCD shows ‘CAL PH’. Press ENT key to
begin first calibration point.
2
Place the electrode in pH 6.86 buffer. Immerse the temperature probe in the
buffer solution if ATC mode is enabled. Immerse the potential matching pin
in the buffer if symmetrical mode is enabled. The buffer annunciator
appears in LCD. Lower display shows pH 6.86 (NIST standard buffer).
Upper display shows the current uncalibrated pH reading. Allow the reading
to stabilize. LCD shows ‘READY’ annunciator when the reading is stable.
Press ENT key to confirm the reading.
3
The pH Monitor moves to the second calibration point. The lower display
shows next standard buffer value (pH 4.01). Use ▲ and ▼ keys to select
your second buffer from one of the preset values: pH 4.01 or 1.68 or 9.18 or
12.45. Remove the electrode from the first buffer, wash and then immerse it
into the second buffer. Allow the reading to stabilize. LCD shows ‘READY’
annunciator when the reading is stable.
Press ENT key (or CAL key) to confirm the reading.
4
The calibration is completed. The pH Monitor re-calculates electrode
properties based on the calibration. The new slope (in mV) is shown in the
upper display and pH reading at 0mV (pH7.00 ± offset) is shown in the
lower display.
Press ENT key to exit from the calibration.
55
The pH Monitor reverts to pH measurement mode.
NOTES:
• To exit from pH calibration mode without confirming calibration, press
▲ and ▼ keys together
• When confirming the buffer measurement, if the measured pH value is
not within ±1.00pH from selected buffer value, the electrode
annunciator
blinks and ERR indicator appears in the display. This
error can also occur if non-standard buffers are used or the electrode
has worn out. If this happens, press both ▲and ▼ keys together to
restart the calibration beginning from Step1
When calibrating with manual temperature compensation, the meter automatically
changes from the preset process temperature to the calibration temperature. After
leaving the calibration mode, the pH Monitor reverts back to process temperature.
4.4 ORP Calibration
The pH Monitor allows a single point ORP calibration. ORP calibration process is
available only when the measurement mode is set to ORP. (Refer Section 5.5 for
switching measurement modes).