User manual EUTECH INSTRUMENTS WATERPROOF PHTESTER 102030BNC

[. . . ] The upper display will be calibrated to the pH standard buffer solution and the lower display will then be toggling in between readings of the next pH standard buffer solution. Rinse electrode in tap water before dipping into next buffer. Figure 4: Example of HOLD Function User Reset Introduction Thank you for selecting our microprocessor waterproof pH tester with USA or NIST buffer set selection. You have one of five models: · pHTestr10 · pHTestr20 · pHTestr30 · pHTestr10BNC · pHSpear This manual provides a step-by-step guide to operate the testers. Note: The calibration mode allows you to perform up to three calibration points before returning to the measurement mode automatically. However, if you opted to have only one or two calibration points, simply skip the remaining calibration points by exiting to the measurement mode by pressing the CAL button. To do a 1 point calibration only, press CAL button at this point to exit to the measurement mode. [. . . ] The display will flash either USA or NIST. Press CAL button to toggle between the two buffer set standards. Press the HOLD/ENT button to confirm the selection of the buffer set. With meter powered off, press HOLD/ENT and ON/OFF at the same time. First release ON/OFF button, then HOLD/ENT button. After buffer selection, whole LCD segment lits up and goes back to measureme nt mode. After the third point calibration, the meter will automatically return to the measurement mode. 1' will be displayed momentarily if the confirmed pH value is not within the pH calibration window. Figure 5: User Reset Sequence Figure 2: Example of pH Calibration Sequence Automatic Temperature Compensation (ATC) ATC feature is available only in pHTestr 10, pH Testr 20 and pH Testr 30. Through its inbuilt temperature sensor, the measurement error due to the changes in electrode sensitivity due to changes in temperature is compensated to give the actual pH reading of the sample measured. pH Testr10BNC and pH Spear has no ATC function and therefore the error should be calculated to derive the actual pH reading of the sample. For these testers, the impact on temperature compensation is 0. 003 pH /°C / pH away from pH 7. For example, if pHSpear is calibrated at room temperature (25 °C) and is measuring sample around pH 4 at around 5 °C. Temperature difference : 25°C - 5°C = 20 °C pH away from neutral : 7pH - 4pH = 3 pH Total error : 0. 003 x 20 x 3 = 0. 18 pH This error value of 0. 18 pH should be taken into consideration to derive the actual pH reading of the sample. pH Measurement Figure 1: Buffer Selection Sequence 1. Press the ON/OFF button to switch the tester on. Dip the electrode about 2 to 3 cm into the test solution. For pHSpear, pierce the penetrating tip electrode through your semi solid sample as per the desired depth. Rotate left and right several times and tilt to ensure sample contact. Note the pH value or press HOLD/ENT button to freeze the reading. To release the reading, press HOLD/ENT again. If you do not press a button for 8. 5 minutes, the tester will automatically shut off to conserve batteries. Temperature Calibration (Only for pHTestr 30) From the measurement mode, 1. Press the HOLD/ENT button to bring the tester to the `HOLD' mode. Press the CAL button for 3 seconds to switch to the °C or °F mode setting selection screen. Pressing the CAL button continuously for 3 seconds allows you to toggle in between the °C and °F mode setting selection screen. Release the CAL button to confirm your mode selection and the display will go to the temperature calibration mode with the upper display flashing. [. . . ] When the tester fails to calibrate or gives fluctuating readings in calibration standards, you need to change the electrode. With dry hands, grip the ribbed tester collar with electrode facing you. Twist the collar counter clockwise (see picture A). Save the ribbed tester collar and O-ring for later use. [. . . ]