Qiwei PH-220W External Electrode Portable pH Meter Malaysia
The Qiwei PH-220W External Electrode Portable pH Meter is designed for convenient pH and temperature measurement in water treatment, aquaculture, industrial maintenance and general laboratory applications.
Unlike an ordinary pocket pH tester with a built-in sensor, the Qiwei PH-220W is equipped with an external wired electrode. The electrode can be lowered into a tank, pond, container or water sample while the main display remains safely in the operator’s hand.
The Qiwei PH-220W is available from stock at MTM Precision Malaysia.
Key Features
0.01 pH resolution
Measures pH and temperature
External wired pH electrode
Three-point pH calibration
Portable and lightweight design
Clear digital display
Suitable for field and indoor measurements
Easier access to tanks, containers and restricted sampling points
Technical Specifications
Model: Qiwei PH-220W
pH Measuring Range: 0.01 to 14.00 pH
pH Resolution: 0.01 pH
Temperature Range: 0 to 50°C
Temperature Resolution: 0.1°C
Calibration: Three-point pH calibration
Electrode Type: External wired electrode
Power Supply: Four 1.5V batteries
Dimensions: Approximately Ø40 × 185 mm
Weight: Approximately 88g
Specifications and supplied accessories may vary according to the latest production batch. Please contact MTM Precision to confirm the current configuration.
Why Choose an External Electrode pH Meter?
A normal pen-type pH meter must be placed directly into the liquid. This can be inconvenient when the water is inside a deep tank, narrow container or difficult-to-reach sampling point.
The external electrode of the Qiwei PH-220W can be immersed in the sample while the operator continues holding and reading the main instrument.
This design is particularly useful for:
Aquaculture ponds and fish tanks
Cooling tower water
Boiler-water samples
Wastewater tanks
Water-treatment plants
Electroplating solutions
Agricultural nutrient solutions
Food and beverage process water
Laboratory water samples
Aquaculture and Fish-Farming Applications
Maintaining the correct pH is important for fish health, feeding conditions and overall water quality.
The Qiwei PH-220W allows aquaculture operators to check different ponds and tanks without carrying a large laboratory instrument. Its external electrode also makes it easier to reach water inside deeper containers.
Cooling Tower and Boiler-Water Testing
Changes in pH may indicate incorrect chemical treatment or changing water conditions.
Routine pH monitoring can help maintenance personnel identify conditions that may contribute to:
Corrosion
Scaling
Ineffective chemical treatment
Unstable water quality
Higher maintenance costs
The Qiwei PH-220W is suitable for convenient routine checks before more detailed laboratory analysis is required.
Industrial Wastewater Monitoring
Factories can use the Qiwei PH-220W for preliminary pH inspection of wastewater and process water.
It can help operators identify unusual pH changes before discharge or further treatment. For regulatory reporting, customers should follow the required laboratory method and local environmental requirements.
How to Obtain a Stable pH Reading
Calibrate the meter using fresh pH buffer solutions.
Rinse the electrode with clean or distilled water.
Place the electrode into the water sample.
Avoid pressing the electrode against the container.
Move the electrode gently and wait for the reading to stabilise.
Record the pH value and sample temperature.
Rinse the electrode after every measurement.
Store the electrode in the correct pH-electrode storage solution.
Do not leave the pH electrode dry for extended periods.
The electrode should also not be continuously stored in distilled or deionised water because this may shorten its service life and cause slow or unstable readings.
Qiwei PH-220W vs Ordinary pH Pen
The main difference is the external wired electrode.
An ordinary pH pen is suitable for testing a cup or small container. The Qiwei PH-220W is more convenient when customers need to measure water inside a tank, pond or restricted sampling location.
The external-electrode design also allows the main instrument to remain away from the liquid during measurement.
Frequently Asked Questions
Does the Qiwei PH-220W measure temperature?
Yes. It can display the pH value together with the measured temperature.
What is the difference between PH-220 and PH-220W?
The PH-220 uses a built-in electrode. The PH-220W uses an external wired electrode, making it more suitable for tanks, ponds and difficult-to-reach samples.
Can it be used for aquaculture?
Yes. It is suitable for routine pH monitoring in fishponds, aquaculture tanks and water-treatment systems.
Does the PH-220W require calibration?
Yes. Like other pH meters, it should be calibrated regularly using suitable pH buffer solutions.
Calibration frequency depends on the required accuracy, frequency of use, type of sample and condition of the electrode.
Why is the pH reading unstable?
Possible causes include:
Dry pH electrode
Dirty or contaminated electrode
Expired calibration buffer
Insufficient stabilisation time
Incorrect electrode storage
Damaged or ageing electrode
Clean and condition the electrode before recalibrating the instrument.
Qiwei PH-220W Available in Malaysia
The Qiwei PH-220W External Electrode Portable pH Meter is available from stock at MTM Precision Malaysia.
Customers may contact us for:
Current stock availability
Product quotation
Supplied accessories
Electrode availability
Operating guidance
pH buffer and storage-solution requirements
Contact MTM Precision
MTM Precision Sdn. Bhd. (744811-A)
Telephone: +603-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com / enquiry@mtmpre.com.my
Website: www.mtmpre.com.my
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor,
Malaysia.
18 Sep 2026
