For full functionality of this site it is necessary to enable JavaScript.
EMIN.ASIA
0

pH Tester Calibration Procedure

04/26/2021 13:50:20

**1\. Range of application** This technical document specifies the calibration of pH tester with glass electrodes of (0-14) pH in measuring range and accurac

1. Range of application

This technical document specifies the calibration of pH tester with glass electrodes of (0-14) pH in measuring range and accuracy of at least 0,02 pH

2. Calibrating techniques

- Outside check

- Technical check

- Measurement check

3. Calibrating instruments

3.1 Standard measuring instrument (s)

Technical Calibration Buffer:


- Range of measurement: (0-14) pH

- Measurement Uncertainty: ≤ 0.01 pH

3.2 Other measuring instrument (s)

Heated Digital Water Bath:


- Range of measurement: (+5 ÷ 99) °C

Standard Humidity, Temperature Meter


- Range of measurement: (-20 ÷ 70) °C

- Accuracy:

  ± 0.2 °C (10 ÷ 40 °C)

  ± 0.4 °C of the remaining

  ± 1%RH (10 ÷ 90) %RH 

  ± 2.0 %RH (of the remaining)

Hygro-Thermometer

- Range of measurement: (0 ÷ 50) °C

- Accuracy: ±0.5 °C

- Range of measurement: (10 ÷95) %RH

- Accuracy: ±3%RH

3.3 Auxiliary Instrument(s)

- Distilled water

- Sprayer

- Tissue, glass cup

4. Conditions for Calibration

Temperature: (25 ± 2) °C

Humidity:  80 %RH

The temperature, as well as the humidity, must be recorded before and after calibration

5. Prepare for Calibration
Prior to the calibration, the following preparations must be done:
- Prepare the Technical Calibration Buffer
- Place the pH tester and Technical Calibration Buffer in the calibration room at least 1 hour prior to calibration. 
- The Technical Calibration Buffer must be kept at constant temperature at least 1 hr at (25 ± 0,2) 0C in Heated Digital Water Bath
- Prior to calibration, immerse the pH tester electrode with distilled water at least 3 hrs in the lab.
Before measuring the pH level of Technical Calibration Buffer, the followings must be met:
- Clean the pH tester’s electrodes with distilled water.
- Dry the electrode with tissue.
The pH tester to be calibrated must be operating at least 15 mins prior to calibration.

6. Begin the calibration
6.1 Outside Check
6.2 Technical Check
6.3 Measurement Check
A pH tester is checked and measured according to the following content, method and requirements:
- Calibrate the pH tester according to the manufacturer's technical documents.
- Check the error with standard pH solutions
- Measure at least 3 times for each pH standard solution. Record the measured results in the record.
- Calculate the error

7. Measurement Uncertainty Evaluation

8. General handling

a. The calibrated pH tester is stamped, certified in paper along with calibration results, and measurement uncertainty.

b. The recommended calibration cycle of pH tester is 12 months.

9. About EMIN's Calibration - Verification - Repair center

EMIN Vietnam’s Calibration and Verification center has been established since 2020 to provide after-sales services. The Calibration and Verification center is thoroughly equipped with technical equipment, followed by the assistance from various equipment manufacturers around the globe. At the center, calibration of specialized equipment is successfully carried out by experienced engineers in EMIN Vietnam, ensuring fast, accurate, reliable procedure to meet the most demanding customers’ requirements). Such technical capacity can only be performed by very few technology businesses in Vietnam. Meanwhile, after tireless effort, the Calibration and Verification center of EMIN Vietnam is officially certified to be accredited by the ISO 17025 standard (Jan, 2021)

If you want your instruments calibrated, please contact:

Equipment Verification - Calibration - Repair Service Center - EMIN Vietnam JSC 

Address: No 203 Nguyen Ngoc Vu Street, Trung Hoa Ward, Cau Giay District, Ha Noi City

Email: services@emin.vn - Hotline: 0968.060.220

Further information about pH tester calibration service can be found here.


Related News

Which Vacuum Pump Should You Choose for a Microbiology Lab to Avoid Affecting Samples?
07/15/2026 14:45:07

Vacuum pumps are utilized in a wide range of microbiology laboratory procedures, from membrane filtration and the aspiration of supernatants following centrifugation to sample concentration and the support of negative-pressure systems. Selecting the appropriate pump not only ensures more stable operational processes but also minimizes the risk of sample contamination, reduces maintenance costs, and extends the equipment's lifespan

QCVN 25:2025/BKHCN Takes Effect: Do Businesses Need to Prepare Electrical Safety Testing Equipment?
07/15/2026 09:15:04

Electrical safety is consistently one of the primary criteria evaluated before electrical or electronic equipment—or industrial components—are released to the market. A product may operate reliably yet still fail to meet requirements if its insulation lacks sufficient durability, its grounding resistance exceeds permissible limits, or leakage current occurs during operation.

Why Is Associated Research Considered an Icon of Hipot Technology?
07/14/2026 09:05:30

When it comes to electrical safety testing equipment specifically Hipot testers—many QA/QC and testing engineers are familiar with the globally renowned brand Associated Research. A subsidiary of the parent company IKONIX, Associated Research (ARI) invented the world's first commercial Hipot tester.

What Is the Standard 3-Phase Voltage? How to Read Cabinet-Mounted Meters Without Errors
07/13/2026 15:09:18

Voltmeters are almost invariably found on the panels of electrical cabinets in factories, power stations, or generator systems. A glance lasting just a few seconds allows an operator to determine whether the power supply is stable or showing signs of abnormality. However, not everyone understands the significance of the displayed readings, particularly regarding three-phase electrical systems.

Distinguishing between ARI’s Hypot, HypotUltra, and HypotMax: Which device is right for your factory?
07/13/2026 09:48:30

Few people realize that the concept of the "Hipot Test"—or electrical safety testing—has long existed within the electrical equipment manufacturing industry. Driven by the growing need to verify the voltage withstand capabilities of conductors, motors, and electrical devices, the industry required a robust and virtually fail-safe method to detect insulation weaknesses before products reached the market.

Stay Updated with Offers

Get exclusive volume discounts, bulk pricing updates, and new product alerts delivered directly to your inbox.

By subscribing, you agree to our Terms of Service and Privacy Policy.

Quick Support

Direct access to our certified experts