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locked to the second buffer value corresponding to the
temperature of the second buffer. When a stable
reading is reached, the WAIT annunciator will stop
flashing and stay off. The instrument will calculate
and compensate for the pH electrode slope deviation
corresponding to the values of the two calibration
buffers. The instrument is now dual point calibrated
and ready for measurements.
After two point calibration, pressing and holding the
[MEA./EFF.] key for about 5 seconds will display the
new electrode efficiency.
2. Calibration with manual temperature compensation in the
pH-AUTOLOCK mode.
2.1 Connect the pH electrode to the BNC connector of the
instrument. The MAN annunciator will be on. Press the
[MODE] key if necessary to go to pH-AUTOLOCK mode.
2.2 Rinse the pH electrode in distilled water and immerse
it 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. ℃
2.3 Press the [STAND] key. The STAND annunciator will be
on and the WAIT annunciator will flash. This means
that the instrument is waiting for a stable reading.
The display will be locked to the buffer value
corresponding to the temperature of buffer 7.00 (or
6.86) as set in 2.2. When a stable reading is reached,
the WAIT annunciator will stop flashing and stay off.
The SLOPE annunciator will start to flash, indicating
that the standardization at buffer 7.00(6.86) is
