Apera Instruments PH20 Instruction 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 [e-mail] 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 is damaged.

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