OHAUS AB23PH - Perform 1-Point Calibration

EN-10 AB23PH Bench pH Meter
Calibration: pH electrodes need to be calibrated with pH standard buffer solution before
a proper pH measurement can be made. Calibration is to display the right pH value
when meter receives the mV value signal from the pH electrode.
Slope: the linear coefficient between mV and pH according to theoretical value (e.g. -
59.16mV/pH @ 25 °C which means 100% slope);
Offset: the mV value when pH value is 7.00. (Theoretical value is 0 mV);
4.1.2 Perform 1-point calibration
When performing calibration, Ohaus recommends using Auto End Point Mode. After
powering the meter on, be sure the top of the screen shows to ensure the meter
is in Auto End point Mode.
4.1.2.1 Auto or Continuous End Point Mode
 Press and hold the Auto-Stop button to change the End Point Mode.
 When in Continuous Mode, to manually reach a pH measurement or calibration
value, you need to press the button Auto-Stop when reading is stable and
displays . Then the reading freezes and blinks 2 times then disappears;
blinks 3 times and freezes on the display.
 When in Auto End Point Mode, the meter determines when the reading is stable
then displays and locks the reading or calibration value automatically, the reading
freezes and blinks 2 times then disappears; blinks 3 times and freezes
on the display.
Note: For the 1-point calibration, if only the offset is adjusted, theoretical 100% slope (-
59.16 mV / pH) will be used.
5 °C
1.67
4.01
7.09
10.25
13.21
10 °C
1.67
4.00
7.06
10.18
13.00
15 °C
1.67
4.00
7.04
10.12
12.81
20 °C
1.68
4.00
7.02
10.06
12.63
25 °C
1.68
4.01
7.00
10.01
12.45
30 °C
1.68
4.01
6.99
9.97
12.29
35 °C
1.69
4.02
6.98
9.93
12.13
40 °C
1.69
4.03
6.97
9.89
11.98
45 °C
1.70
4.05
6.97
9.86
11.84
50 °C
1.71
4.06
6.96
9.83
11.70