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probe to stabilize. Press the [STAND] key. The STAND
annunciator will be on and the SLOPE annunciator will
flash, indicating that 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) as measured in 3.2. If the
reading still drifts, repeat 3.3 until a stable
reading is obtained.
3.4 Remove the pH electrode and ATC/Temp probe from
buffer 7.00(6.86). Rinse them in distilled water and
immerse them in buffer 4.00(4.01) or 9.18(10.01). The
instrument will display the temperature of the second
buffer.
3.5 Allow sufficient time for the pH electrode and
ATC/Temp probe to stabilize. Press the [SLOPE] key.
The SLOPE annunciator will stop flashing and stay on.
The instrument will display the second buffer value
corresponding to the temperature of the second buffer,
as measured in 3.4. If the reading still drifts,
repeat 3.5, until a stable reading is obtained. 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.
4. Calibration with manual temperature compensation in the
pH mode.
4.1 Connect the pH electrode to the BNC connector of the
