8. If you need to test an acid solution, prepare the pH 4 calibration solution.
9. Use the probe to stir the solution for a while and then wait without stirring until a stable value
is displayed on the LCD display.
10. To start the calibration process, press and hold the
bol "CAL" appears on the LCD display. The pH value 4.01 (or 10.01 for the alkaline calibra-
tion solution) will start to flash on the LCD display.
11. The pH value will stop flashing and the display will show the slope of the measurement
probe in %, followed by "SA" and "End". The two-point calibration process is now complete.
The meter will automatically revert to measuring mode. If the calibration process fails, "Err"
will be displayed instead of "SA".
12. To determine the slope in an alkaline direction (if you want to measure an alkaline solution),
use the calibration solution with a pH value of 10.01 to calibrate the device. Repeat the
above steps starting with the neutral calibration solution.
13. After calibration with the pH4 or pH10 calibration solution, the slope of the electrode will be
displayed in % on the LCD display.
14. To conduct a 2 or 3-point calibration, start with the pH 7 calibration solution and then cali-
brate with the pH4 or pH10 calibration solutions.
If the slope of an electrode (in %) is less than 70 % or more than 130 %, the measure-
ment probe must be replaced. The optimal slope is 100 %.
The standard for the pH calibration points can be set to "USA" or "NIST". The calibra-
tion points for "USA" are 1.68, 4.01, 7.00, 10.01 and 12.45. The calibration points for
"NIST" are 1.68, 4.01, 6.86, 9.18 and 12.45. For more information on selecting the
desired standard, see section "i) Advanced settings".
Redox calibration
2
The measurement probe does not need to be calibrated for measurements with a
redox probe. However, you can use a standard ORP solution to verify that the probe
is functioning correctly.
•
If you are using a redox probe, connect the redox probe to the input (14).
COND, TDS, salt calibration (for product with item no. 1762763)
3
1. Make sure that the conductivity cell is connected to the conductivity cell input (13). The tem-
perature sensor must also be in the solution if you want to use the automatic temperature
compensation (ATC).
2. Remove the soaking bottle. Press the
button (7) until the calibration sym-
button (7) to switch the meter on.
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