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instrument. The MAN annunciator will be on. Press the
[MODE] key for the LCD to indicate pH and for the AUTO
annunciator to be off.
4.2 Rinse the pH electrode in distilled water and immerse
in buffer 7.00(6.86). Set the instrument to display
the temperature of the buffer by pressing the [
∆
]
and [
∇
] keys. The displayed temperature must be
less than 60℃.
4.3 Allow sufficient time for the electrode to stabilize.
Press the [STAND] key. the STAND annunciator will be
on and the SLOPE annunciator will start to flash,
indicating that the standardization at buffer 7.00
(6.86) is completed and the instrument is ready to be
sloped at a second buffer. The instrument will display
the buffer value corresponding to the temperature of
the buffer 7.00(6.86) set in 4.2. If the reading still
drifts, repeat 4.3 until a stable reading is obtained.
4.4 Remove the pH electrode from buffer 7.00(6.86), rinse
with distilled water and immerse it in buffer
4.00(4.01) or 9.18(10.01). Set the instrument to the
temperature of the 2nd buffer as in 4.2. The displayed
temperature must be less than 60. ℃
4.5 Allow sufficient time for the pH electrode to
stabilize. Press the [SLOPE] key. the SLOPE
annunciator will stop flashing and stay on. The
instrument will display the value of the second buffer
corresponding to the temperature of the second buffer
as set in 4.4. If the reading still drifts, repeat
4.5, until a stable reading is obtained. The
instrument will calculate and compensate for the pH
electrode slope deviation corresponding to the values
