MODEL 5081-A
SECTION 13.0
CALIBRATION - pH
13.2 PROCEDURE — AUTO CALIBRATION USING THE REMOTE CONTROLLER
1. Verify that auto calibration has been enabled. See Section 7.8.
2. obtain two buffer solutions. Ideally, the buffer pH values should bracket the range of pH values to be meas-
ured.
3. Remove the sensor from the process liquid. If the temperature of the process and buffer are appreciably dif-
ferent, place the sensor in a container of tap water at the buffer temperature. do not start the calibration until
the sensor has reached the buffer temperature. thirty minutes is usually adequate.
4. Press CAL on the remote controller.
5. Press NEXt until the
PH CAL
submenu appears. Press ENtER.
6. the
AUtO CAL
submenu appears. Press ENtER.
7. the
CAL bF1
prompt appears. Rinse the sensor and place it in the first
buffer. Be sure the glass bulb and reference junction are completely
submerged. Swirl the sensor. the main display will show the pH of the
buffer based on the previous calibration. Press ENtER.
8.
bF1
flashes until the pH reading meets the stability criteria programmed
in Section 7.8.
9. once the reading is stable, the display changes to look like the figure
at left. the flashing number is the nominal pH, that is, the pH of the
buffer at 25°C. If the flashing number does not match the nominal pH,
press
é
or
ê
until the correct pH appears. Press ENtER to save.
10. the
CAL bF2
prompt appears. Remove the sensor from the first buffer.
Rinse the sensor and place it in the second buffer. Be sure the glass
bulb and reference junction are completely submerged. Swirl the sen-
sor. the display will show the pH of the buffer based on the previous
calibration. Press ENtER.
11.
bF2
flashes until the pH reading meets the stability criteria programmed
in Section 7.8.
12. once the reading is stable, the display changes to look like the figure
at left. the flashing number is the nominal pH, that is, the pH of the
buffer at 25°C. If the flashing number does not match the nominal pH,
press
é
or
ê
until the correct pH appears. Press ENtER to save.
13. Press RESEt to return to the main display.
CALIBRAtE
bf1
EXIt
ENtER
CALIBRAtE
PH Cal
EXIt
NEXt ENtER
CALIBRAtE
CAL bF1
EXIt
NEXt ENtER
CALIBRAtE
AUtO CAL
EXIt
NEXt ENtER
CALIBRAtE
bF2
EXIt
NEXt ENtER
CALIBRAtE
CAL bF2
EXIt
NEXt ENtER
CALIBRAtE
bf1
EXIt
ENtER
4
.01
CALIBRAtE
bf2
EXIt
ENtER
10
.00
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