Before you begin:
Condition your MicroDirect pH30 electrodes by immersing it in electrode storage solution or tap
water or at least 30 minutes before use. DO NOT use de-ionized water.
pH Buffer Set Selection
Your tester features USA (pH 4.01, pH 7.00 and pH 10.01) or
NIST (pH 4.01, pH 6.86, and pH 9.18) standards. Select either one to suit your requirements.
1. While pressing the HOLD/ENT button, switch on the tester by pressing the ON/OFF button.
2. Release the HOLD/ENT button. The display will flash either USA or nSt.
3. Press CAL button to toggle between the two buffer set standards.
4. Press the HOLD/ENT button to confirm the selection of the buffer set.
pH Calibration
Calibration should be done regularly, preferably once a week. You can calibrate up to three
points using either the USA or the nSt buffer set standards.
1. Press ON/OFF button to switch unit on.
2. Dip electrode about 2 to 3 cm into the pH standard buffer solution.
3. Press the CAL button to enter calibration mode. The ‘CAL’ indicator will be shown. The upper
display will show the measured reading based on the last calibration while the lower display will
indicate the pH standard buffer solution.
Note:
All testers have dual display during calibration mode
Note:
To abort calibration, press the ‘CAL’ button.
4. Allow about 2 minutes for the tester reading to stabilize before pressing the HOLD/ENT button
to confirm the first calibration point. 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.
5. Repeat with other buffers if necessary. Rinse electrode in tap water before dipping into next
buffer.
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.
pH Measurement
1. Press the ON/OFF button to switch the tester on.
2. Dip the electrode about 2 to 3 cm into the test solution. Stir and let the reading stabilize.
3. Note the pH value or press HOLD/ENT button to freeze the reading. To release the reading,
press HOLD/ENT again.
4. Press ON/OFF to turn off tester. If you do not press a button for 8.5 minutes, the tester will
automatically shut off to conserve batteries.
HOLD Function
This feature lets you freeze the display for a delayed observation
1. Press HOLD/ENT button to freeze the measurement. A ‘HOLD’ indicator will be displayed and
the measurement will be frozen.
2. Press HOLD/ENT again to release the measurement. The ‘HOLD’ indicator will not be displayed
anymore indicating the held measurement is released.
User Reset
You can reset the pH calibration to the factory default by using the user reset function.
Buffer set selection and temperature user calibration (pHTester30) are not affected by the user
reset function.
1. Switch off the tester.
2. While pressing the ‘CAL’ button, press and release the ON/OFF button to enter the ‘User
Reset’ selection menu. The screen will display ‘rSt’ on the bottom display with a flashing ‘nO’
selection.
3. Use the ‘CAL’ button to toggle between ‘nO’ and ‘YES’ selection.
• nO deactivates reset selection
• YES activates the reset selection
4. Press the HOLD/ENT button to confirm the selection made.
5. If you have selected ‘YES’, the unit will show ‘CO’ momentarily and proceed to the measure-
ment mode with the calibration reset back to factory default value.
6. If ‘nO’ is selected, the unit will proceed to the measurement mode without any calibration
reset performed.
Automatic Temperature Compensation (ATC)
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.
Temperature Calibration
From the measurement mode,
1. Press the HOLD/ENT button to bring the tester to the ‘HOLD’ mode.
2. 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.
3. Release the CAL button to confirm your mode selection and the display will go to the tem-
perature calibration mode with the upper display flashing. The upper display shows the current
measured temperature reading based on the last set offset and the lower display shows the
current measured temperature reading based on factory default calibration.
4. Dip the tester into a solution of known temperature and allow time for the in built tempe-
rature sensor to stabilize.
5. Press the HOLD/ENT button to set the upper display to the temperature value of the solu-
tion.
6. Once the new temperature setting is reached, the new value is automatically confirmed and
returns to the measurement mode if no button is pressed after 5 seconds.
Notes: To exit this program without confirming the calibration, press the CAL button before the
automatic confirmation takes place.
GB
• Large Screen
• Waterproof
pH / Tempe-
rature Tester
• Double Junc-
tion
Instruction
manual
Fahrenheit
pH30
