Lutron Electronics PH-222 - Page 9

pH 4 calibration
1)Rinse the electrode in distilled water.
2)Power on the instrument by pressing the " Power button "
( 3-2, Fig. 1 ).
3)Press the " Hold button " ( 3-3, Fig. 1 ) once.
the display will show the " HOLD " symbol.
Press the " button " ( 3-4, Fig. 1 ) once, the display▼
will show following screen in sequence.
screen 1
CAL flashing
screen 2
7.00
CAL
4)Press the " button " ( 3-4, Fig. 1 ) once, the display▼
will show :
screen 3
4.00
CAL
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