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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 4.1. "
Er 2
" may appear if the [SLOPE] key is pressed
before the electrode settles to within 30% of the buffer
value. Allow sufficient time for the electrode to stabilize
before taking any action
pH MEASUREMENTS
The STAND and SLOPE annunciators must be on. This means that
the instrument is dual point calibrated and is ready for
measurements.
1. Measurement with ATC/Temp probe in the pH-AUTOLOCK
mode.
1.1 Connect the pH electrode and ATC/Temp probe to the top
of the
instrument . The ATC annunciator will be on.
1.2 Press the [MODE] key until the LCD indicates pH mode
and the
AUTO annunciator is on.
1.3 Rinse the pH electrode and the ATC/Temp probe with
distilled
water and immerse them in the sample to be measured.
