User Manual

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stable and icon displays, then press < CAL >, LCD flashes
7.00 pH, calibration finishes after several seconds and then
flashes, indicating the 1
st
point calibration has been
finished and the 2
nd
point calibration begins.
4.2.3. Take out pH electrode, rinse it in pure water, allow it to dry and submerge it in pH4.00
buffer solution. Stir the solution briefly and allow it to stay in the buffer solution until reading
is stable and icon displays, then press < CAL >, LCD flashes 4.00pH, calibration
finishes after several seconds and then flashes, indicating the 2
nd
point calibration
has been finished and the 3rd point calibration begins.
4.2.4. Take out pH electrode, rinse it in pure water, allow it to dry
and submerge it in pH 10.01 buffer solution. Stir the solution briefly
and allow it to stay in the buffer solution until reading is stable and
icon displays, then press < CAL >, LCD flashes 10.01pH,
calibration finishes while displaying a stable pH and temperature value. icon
appears on the screen, indicating 3 points calibration has been finished. See picture (4-1).
4.2.5. Notes:
(a) The meter can perform 1 point, 2 points or 3 points of automatic calibration. When the 1
st
point calibration finished, press < ENTER > key to confirm and enter measuring mode.
icon for one-point calibration will appear on the lower left corner of the LCD. When the
desired measuring accuracy is ±0.1pH, choose one kind of buffer solution according to the
measuring range and then proceed with one-point calibration.
(b) When the 2nd calibration finishes, press < ENTER > key to confirm 2 points calibration
and enter into measuring mode. Icons or for 2 points calibration will appear on
the lower left corner of the LCD. If measurement is within acid range, you can choose pH4.00
and pH7.00 for calibration. If the measurement is within alkalinity range, you can choose
pH7.00 and pH10.01 for calibration.
(c) For high accuracy measurement, it is better to choose 3 points calibration if: the
measuring range is wide, the electrode is ageing, or the electrode has been inactive for a