pH Meters
A pH meter is an instrument designed to measure the hydrogen-ion level in water-based solutions. It is sometimes also referred to as a pH tester or detector. A pH meter measures the acidity and alkalinity levels in liquids, and is also referred to as a potentiometric pH meter.
This scientific instrument functions by measuring the voltage between two electrodes. The results are displayed by converting this information into a pH value. The term 'pH' refers to a unit of measurement with a range between zero and fourteen. The mathematical symbol 'p' represents potential, while the 'H' is the symbol for hydrogen.
pH Meter Types
Pocket pH Meters
Pocket pH meters are devices with LCD displays which can deliver fast and accurate readings. They are lightweight and easy to transport, making them ideal for field use. Pocket pH meters are popular with students and researchers in testing and research applications. Pocket pH meters often feature automatic buffer recognition, easily replaceable electrode modules and long-lasting battery life.
Portable pH Meters
Portable pH meters are handheld devices that are built for field use. These rugged meters contain Bluetooth technology which allows information to be downloaded to a mobile or tablet. Multi-parameter meters are suited to robust industrial environments, while PC connectivity allows for data collection and analysis.
Benchtop pH Meters
Bench meters are large, high-precision instruments that can be desk or wall-mounted. They often come with advanced features such as Bluetooth technology and built-in printers. Data transfer to PCs or tablets is seamless, making them perfect for professional or laboratory use.
Test strips
Test strips indicate the strength or weakness of a chemical presence by colour saturation. Paleness indicates that concentration levels are low, while high saturation shows the reverse. Adding reagents to the solution allows for the colour to be tested against a colour chart.
Pen pH Meters
Pen pH meters are compact, all-in-one devices offering basic functionality and portability that are usually the cheapest found on the market. Pen pH meters are used in the hydroponics, food manufacturing, as well as pool and spa maintenance industries.
Digital pH Meters
Digital pH meters refer to a wide category of measuring devices with LCD screens and often have data-logging functions. The term can refer to larger, benchtop units with advanced features or handheld pH meters meant for field work.
pH Meters vs. pH Testers
A pH meter is a potentiometric device that defines pH levels by measuring the voltage between two electrodes, while a pH tester typically refers to test strips that use the colorimetric method to determine pH.
Here are some of their other key differences:
- Resolution: pH testers have lower resolutions than pH meters. If you need to measure minute changes in quantity, it is better to stick with pH meters.
- Accuracy: For pH testers, the results are produced by colours that correspond to a colour chart. However, colour perception is subjective and can vary based on lighting conditions. For this reason, pH meters are able to produce more consistent and accurate results.
- Repetitive tests: Monitoring pH levels over time requires the continuous logging of pH values. This is not possible with single-use pH testers, but easily accomplished by digital pH meters.
Industrial Applications of pH Meters for Water
pH meters are widely deployed in a range of industrial applications.
Harsh environments
In wastewater treatment facilities and chemical processing plants, pH meters are housed in robust, chemically resistant casings with specialised electrodes able to withstand extreme temperatures, pressures, and corrosive substances. Such meters ensure compliance with environmental regulations and safety.
Biological micro-environments
Miniature pH meters with microelectrodes are used to measure pH in very small sample volumes, such as cellular cultures or localised biological processes. They are often integrated into microfluidic devices for precise spatial and temporal control.
Medical and research laboratories
Benchtop pH meters are used to accurately measure and monitor pH in liquids during chemical reactions, biological assays, and material science experiments.
Quality control
pH meters ensure product consistency and safety by regularly checking pH levels of raw materials, in-process samples and finished goods. They are often integrated into automated systems for high-throughput analysis.
Agriculture
Portable or integrated soil pH meters are used to assess soil acidity or alkalinity, so farmers are able to determine if adjustments are needed to improve nutrient availability and overall crop health.
Municipal water supplies
Continuous monitoring of pH levels in water treatment plants and distribution networks confirms that neutral values are maintained. This ensures water is safe for consumption.
Breweries
pH meters are deployed to ensure acidity remains at optimum levels for enzyme activity, yeast health and fermentation. This promotes a consistent flavour profile and optimum quality.
Swimming pools
Automatic pH regulators are used to continuously and maintain monitor pool water pH. pH levels between 7.2 and 7.8 are essential for the comfort of swimmers and sanitation.
Food industry
Specialised pH meters measure the pH levels of food products to control taste, texture, shelf-life and prevent spoilage, ensuring product safety and quality.
pH Meter Manufacturer, Supplier & Distributor in Australia
RS is your go-to supplier and distributor for pH level testers and digital pH meters in Australia. We carry high-quality products from industry leaders like Endress+Hauser, Hanna Instruments and Extech. Our pH checkers, readers and detectors are available at a range of affordable prices, and we also carry other environmental testing peripherals like anemometers and hygrometers. Buy reliable measuring devices online now and enjoy next-day delivery.
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