Oakton pHTestr 20 Instruction Manual

This Instruction Manual is also available for download on our Web-site: eutechinst.com or 4oakton.com
Part of Thermo Fisher Scientific
INSTRUCTION MANUAL
pHTestr 10, 20, 30, 10BNC, Spear
Large Screen
Waterproof pH / Temperature Testr
Double Junction
Introduction
Thank you for selecting our waterproof pH Testr. This manual serves the following
(5) models:
• pHTestr 10 (Eutech PHTEST10 / 01X366901 / Oakton 35634-10)
• pHTestr 20 (Eutech PHTEST20 / 01X366902 / Oakton 35634-20)
• pHTestr 30 (Eutech PHTEST30 / 01X366903 / Oakton 35634-30)
• pHTestr 10BNC (Eutech PHTEST10BNC 01X366904 / Oakton 35634-14)
• pH Spear (Eutech PPHSPEAR 01X366920 / Oakton 35634-40)
This manual provides a step-by-step guide to operate the Testrs.
Before you begin:
Condition your pHTestr 10, 20, 30 electrodes by immersing it in electrode storage solution
or tap water for at least 30 minutes before use. DO NOT use de-ionized water.
Ensure that your pHSpear electrode is always soaked in the electrode storage solution or tap
water via its protective cap.
Note: For pHTestr10BNC, please refer to the pH electrode's instruction manual.
pH Buffer Set Selection
Your Testr 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 Testr by pressing the
ON/OFF button.
2. Release the HOLD/ENT button. The display will flash either USA or NIST.
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.
With meter powered
off, press
HOLD/ENT
and ON/OFF
at the same
time. First release
ON/OFF button, then
HOLD/ENT button.
Figure 1: Buffer Selection Sequence
pH Calibration
Calibration should be done regularly, preferably once a week. You can calibrate up to three
points using either the USA or the NIST 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 Testrs have dual display during calibration mode
Note: To abort calibration, press the 'CAL' button.
4. Allow about 2 minutes for the Testr 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.
Figure 2: Example of pH Calibration Sequence
pH Measurement
1. Press the ON/OFF button to switch the Testr on.
2. Dip the electrode about 2 to 3 cm into the test solution. Stir and let the reading
stabilize. For semi-solid samples using pHSpear, rotation is ideal for sample contact.
CAUTION: Testing dry samples is not accurate and can lead to sensor damage
After buffer
or breakage. Soils must be wet and free of par ticulates that may scratch the glass
selection,
sensor. Excessive force into dry samples can cause glass breakage.
whole LCD
segment lits up
3. Note the pH value or press HOLD/ENT button to freeze the reading. To release
and goes back
the reading, press HOLD/ENT again.
to measureme
4. Press ON/OFF to turn off Testr. If you do not press a button for 8.5 minutes,
nt mode.
the Testr 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 (pHTestr30) are not affected by the user
reset function.
1. Switch off the Testr.
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
measurement mode with the calibration reset back to factory default value.
To do a 1 point calibration
6. If 'nO' is selected, the unit will proceed to the measurement mode without any
only, press CAL button at this
point to exit to the calibration reset performed.
measurement mode.
Otherwise, proceed to second
With meter powered
buffer for a second buffer for
off, press CAL and
a second point calibration.
ON/OFF at the same
time. First release
ON/OFF button, then
To do a 2 point calibration only, press
CAL button.
CAL button at this point to exit to the
measurement mode. Otherwise,
proceed to third buffer for a third
buffer for a third point calibration.
ATC - Automatic Temperature Compensation
After the third point calibration, the meter will
automatically return to the measurement
(Only for pHTestr 10, pHTestr 20 and pHTestr 30)
mode. At any point, an error message 'Er. 1'
Through its in-built temperature sensor, the measurement error due to the changes in electrode
will be displayed momentarily if the confirmed
sensitivity due to changes in temperature is compensated to give the actual pH reading of
pH value is not within the pH calibration
window.
the sample measured.
MTC - Manual Temperature Compensation
(Only for pHTestr 10BNC, pH Spear)
The MTC range is 0 to 50.0 °C (32.0 to122.0 °F). User reset will set temperature to default
value 25°C or 77°F.
While in the measurement mode,
1. Press the HOLD/ENT button to bring the Testr to the 'HOLD' mode.
2. Press the CAL button continuously to switch to the °C or °F mode setting
selection screen.
3. Release the CAL button to confirm your mode selection and the display will go to
the manual temperature calibration mode with the upper display flashing. The
upper display shows the adjustable temperature value and the lower display shows
the last set temperature offset.
4. Press the HOLD/ENT button to set the upper display to the temperature value of
your sample.
5. Once the setting is reached, release the HOLD/ENT button. 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.
Figure 4: Example of HOLD Function
After reset, whole
LCD segment lits up
and goes back to
measurement mode.
Figure 5: User Reset Sequence