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values of the two calibration buffers. The instrument is dual
point calibrated and is now ready for measurements.
After two point calibration, pressing and holding the
[MEA./EFF.]
key for about 5 seconds will display the new electrode
efficiency.
If "
Er 2
" is displayed, check that the correct buffer is used
and that the slope of the electrode is not off by more than
30% from the theoretical slope. Only buffers 4.01, 9.18 or
10.01 may be used for slope calibration. Replace the buffer
and/or the pH electrode. Press the [CLEAR] key and repeat
from 2.1. "
Er 2
" may appear if the [SLOPE] key is pressed
before the electrode and the ATC/Temp probe settle to
within 30% of the buffer value. Allow sufficient time for the
electrode and ATC/Temp probe to stabilize before taking
any action
3. Calibration with ATC/Temp probe in pH mode.
3.1 Connect the pH electrode and the ATC/Temp probe to the
top of
the instrument. The ATC annunciator will be on. Press the
[MODE] key for the LCD to display pH and the
AUTOLOCK annunciator to be off.
3.2 Rinse the pH electrode and ATC/Temp probe in distilled
water
and immerse in pH buffer 7.00 (or 6.86). the instrument will
display the buffer temperature.
3.3 Allow sufficient time for the electrode and ATC/Temp
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 (or 6.86)
