Apera Instruments PH20 User manual

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PH20 Value pH Tester
Instruction Manual
APERA INSTRUMENTS, LLC
www.aperainst.com
v 3.3

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1. Battery Installation
Please install batteries according to the following steps. *Please note the correct
direction of battery installation:
The Positive Side (“+”) OF EVERY SINGLE Battery MUST FACE UP.
(WRONG INSTALLATION OF BATTERIES WILL CAUSE DAMAGE TO THE
TESTER AND POTENTIAL HAZARDS!)
2. Keypad Functions
■Short press------- < 2 seconds
■Long press-------- > 2 seconds
1. Short press to turn on, long press to turn off;
2: When turned off, long press to enter setup;
3: In mode setting, short press to change
parameter;
1.When turned on, long press to enter calibration
mode.
2.In calibration mode, short press to confirm
calibration;
3.In mode setting, short press to confirm parameter
selection.
Diagram - 1

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3. Complete Kit
Things needed in addition to what’s in the box
A clean cup, distilled water (8-16oz), and tissue papers for rinsing and drying the
probe.
4. Calibration
4.1 If it’s first time use or the tester hasn’t been used for a long time, pour some
pH 4.00 solution to the Fill line in the probe cap, soak probe for about 15 minutes
to hydrate the pH sensor.
4.2 Short press to turn on. Rinse in distilled water; shake the meter in the
air and use tissue paper to dap off excess water.
4.3 Long press to enter calibration mode; Short press to exit.
4.4 Insert the probe in the 7.00 pH calibration solution; Stir gently;
leave it to stand; Wait for the smiley face to appear and
stay on the screen (see Diagram 3); short press to complete
1st point calibration, tester returns to measurement mode;
calibration icon displays on button left side of the screen.
4.5 Rinse probe in distilled water. Long press to enter calibration
mode; insert the probe in the pH 4.00 calibration solution, stir gently; leave it
Diagram - 2
Diagram - 3

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to stand; wait for the smiley face to appear and stay on the screen; then
short press to complete the 2nd point calibration,
tester returns to measuring mode, calibration icons display on
bottom left side of LCD.
■Notes
a) Tester will automatically recognize pH buffer solution, users can choose
calibration points: 1 point, 2 points, or 3 points. But the 1st point calibration
must be in calibration solution of 7.00 pH, then followed by 2nd or 3rd point
calibration. For details, please refer to the following table:
Calibration Solution
Calibration
Indication icon
Recommended Accuracy
and Range
1-point
Calibration
7.00 pH
Accuracy ≥0.1pH
2-point
Calibration
7.00 pH and 4.00 pH
Measuring Range <7.0
pH
7.00 pH and 10.01 pH
Measuring Range>7.0
pH
3-point
Calibration
7.00 pH, 4.00 pH
and 10.01 pH
Wide measuring range
b) Automatic self-diagnostic information: if measured value is far off to the
preset range, LCD will display “Er1”; In calibration mode, if the measured
value hasn`t been stable, i.e. has not been staying on LCD, pressing
will cause LCD to display “Er2”.
5. Measurement
5.1 Short press to turn on the tester. Rinse probe in distilled water, shake
the meter in the air and dap it with tissue paper to remove excess water.
5.2 Stir probe in sample solution gently, leave it to stand. Get readings after
comes up and stays.

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■Notes
If you see some white crystalline solid leaked out of the pH probe, that’s the reference
solution (3M KCL) inside the probe. It is NOT a sign of any defective issue. It is a normal
phenomenon when the probe is stored dry for a period of time. It proves that the
junction of the probe is working well. Users can simply rinse the probe in distilled water
to remove the solids and use the tester as usual.
After each test, users should rinse the pH probe thoroughly with distilled water or
purified water.
For the premixed pH calibration buffer solutions, we recommend replacing them after
10 to 15 times of use to keep its accuracy.
This meter will NOT give accurate or stable pH readings when testing distilled or
deionized water. This is because distilled or deionized water do not have enough ions
present for the electrode to function properly. To measure distilled or deionized water’s
pH, users need to use a specialized instrument. Contact us at [email protected] for
more details. When testing purified water like spring water or drinking water, it will
take longer for the readings to get stabilized (typically 3-5 minutes) because there is
very few ions left to be detected by the sensor in those purified water.
Do NOT store probe in purified water because that will cause permanent damage to
the pH probe. Purified water is only recommended for rinsing the probe. The probe
should be stored in 3M KCL pH electrode storage solution (SKU AI1120) for best
accuracy or stored in the pH 4.00 calibration solution as an alternative if storage
solution is not handy.
Do NOT use any other brand’s storage solutions because different chemicals may be
used and potential permanent damage could be caused to the meter.
Storing the probe dry will NOT cause permanent damage to it. It will only temporarily
cause the probe to lose its sensitivity, which can always be restored by soaking in the
storage solution or pH4.00 calibration solution.
6. Parameter Setting
6.1 Setting Schedule
Prompt
Mark
Parameter Setting Items
Code
Factory
Default
P1
Select pH buffer
USA –NIST
USA
P2
Select Temperature Unit
˚F – ˚C
˚F
P3
Back to Factory Default
No –Yes
No

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6.2 Parameter Setting
When turned off, long press to enter setup →short press to switch
P1-P2-P3→Short press , parameter flashing→short press to choose,
short press to confirm parameter selection→Long press to go back to
measurement mode.
6.3 Parameter Setting Instruction
Select standard pH buffer solution (P1): There are two options of standard buffer
solutions: USA series and NIST series as the following chart:
Icons
pH standard buffer solution series
USA series
NIST series
Three-Point
calibration
1.68 pH and 4.00 pH
1.68 pH and 4.01 pH
7.00 pH
6.86 pH
10.01 pH and 12.45 pH
9.18 pH and 12.45 pH
6.4 For the self-diagnosis information, please refer to the table below:
Symbol
Self-Diagnosis information
How to fix
Wrong pH calibration solution, which
exceeds the recognizable range of
the meter.
1. Check if calibration solution is correct
2. Check if probe isdamaged.
3. Check if there is any air bubble in the
glass bulb sensor
Is pressed before measurement
is stable ( appears and stays)
Wait for the smile icon to appear and
stay, then press
* If you find any air bubble in the glass bulb of the pH sensor, simply shake the probe for a few times
to remove it. The existence of an air bubble in the glass bulb will significantly decrease the accuracy
of measurement.

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* The 1st point calibration must be 7.00 pH. Perform the 2nd point calibration (4.00 pH) immediately
after the 1st point. Do NOT turn off the meter before you conduct 2nd point calibration. If the meter is
turned off after 1st point calibration, users will need to restart the calibration process with the 7.00 pH
and the 4.00 pH following after. Calibrating directly in pH 4.00 after turning meter off and back on will
cause Er1.
7. Technical Specifications
8. Tester Functions
8.1 Calibration points indication:
8.2 Stable Measurement: appears and stays on the screen
8.3 Self-Diagnostic information: Er1, Er2
8.4 Low-Voltage warning: flashes, reminder of battery replacement
8.5 Auto Power-Off in 8 minutes if no operation.
Go to support.aperainst.com to find tutorial videos and FAQ articles, or submit a
ticket if you have any questions regarding the using meter.
pH
Range
0 - 14.0 pH
Resolution
0.1 pH
Accuracy
±0.1 pH
Calibration Points
1 - 3 points
Automatic Temperature Compensation
0 –50˚C (0 –122˚F)
Temp.
Range
0 –50˚C (0 – 122˚F)
Resolution
0.1 ˚C
Accuracy
±0.5˚C

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9. Warranty
We warrant this instrument to be free from defects in material and workmanship
and agree to repair or replace free of charge, at option of APERA INSTRUMENTS,
LLC, any malfunctioned or damaged product attributable to responsibility of APERA
INSTRUMENTS, LLC for a period of two years from the delivery (a six-month limited
warranty applies to probes). This warranty does not apply to defects resulting from
actions such as misuse (violation of the instructions in this manual or operations in
the manner not specified in this manual), improper maintenance, or unauthorized
repairs. Warranty period is the time limit to provide free service for the products
purchased by customers, not the service life of the tester or probe.
APERA INSTRUMENTS, LLC
Address: 6656 Busch Blvd, Columbus Ohio 43229
Tel: [phone]
Email: [e-mail]
Website: www.aperainst.com