pH Meters

A pH meter is an instrument designed to measure the hydrogen-ion level in water based solutions. A pH meter indicates the acidity and alkalinity and is sometimes also referred to as a potentiometric pH meter.

A pH meter works 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 measure with a range between zero and fourteen. The mathematical symbol 'p' represents potential, while the 'H' is the symbol for hydrogen.


    Harsh environments

    Biological micro-environments

    Laboratory experimentation

    Quality control


    Municipal water supplies

    Brewing industry

    Swimming pools

    Food industry

Replacement parts are available, such as pH electrodes made from a special glass composed of alkali metal ions which sense the hydrogen ion concentration. As the electrode ages, the glass electrodes resistance changes.

pH meter calibration is required as electrodes run down eventually and need to be calibrated on a regular basis. Calibration in a pH buffer solution which has a constant pH value should always start with buffer 7.0 as this is point ’zero’. The pH scale has an equivalent mV scale from +420 mV to -420 mV. The buffer solution is available as a pre-mixed liquid or dry powder capsules.

What types of meters are there?

Pocket testers are a device with an LCD display which can deliver fast and accurate readings. They are lightweight and easy to transport making them ideal for field use. Pocket tester meters are popular with students and researchers which they use for measurements in test tubes and vials. Features of a pocket tester meter include automatic buffer recognition, easily replaceable electrodes and thousands of hours of battery life.

Portable pH meters are handheld and lightweight. They contain Bluetooth technology which allows the information to be downloaded to a mobile or tablet. Multi-parameter meters are suited to robust industrial environments and have PC connectivity.

Bench meters are accurate, easy to use and available with Bluetooth technology and built-in printers. It is easy to transfer data via Bluetooth onto a mobile or tablet, or onto a PC via a USB cable.

Test kits measure the strength or weakness of a chemical presence by the degree of colour saturation. If pale then the concentration is low, if strong then the concentration is high. Adding the reagent to the compound allows the colour to be tested against a colour chart.

Read more Read less


Viewing 21 - 25 of 25 products
Results per page
Description Price Maximum pH Minimum pH pH Resolution Best pH Accuracy Maximum Temperature Measurement Minimum Temperature Measurement Temperature Measurement Resolution Best Temperature Measurement Accuracy Maximum Conductivity Minimum Conductivity Conductivity Resolution Best Conductivity Accuracy Maximum Oxidation Reduction Potential Minimum Oxidation Reduction Potential
RS Stock No. 327-5033
Mfr. Part No.201020/51-18-07-22-120/837,
+12pH 0pH - - +80 °C -5°C - - 5µS/cm 0.1 μS/cm - - - -
RS Stock No. 726-2696
Mfr. Part No.HI-991001N
+16pH -2pH 0.01pH ±0.02pH +105 °C -5°C 0.1°C ±0.5 °C - - - - - -
RS Stock No. 454-6960
Mfr. Part No.HI 3811
- - - - - - - - - - - - - -
RS Stock No. 195-0936
Mfr. Part No.CA 10101
16pH -2pH 0.01pH - +120 °C -10°C 0.1°C - - - - - - -
RS Stock No. 195-0938
Mfr. Part No.CA 10001
14pH 0pH 0.01pH - +60 °C 0°C 0.1°C - - - - - - -
Related Products
Di St 3: Water conditioning (softener, demineralisation, aquariums, ...
Di St 3: Water conditioning (softener, demineralisation, aquariums, pollution control),Di St 4: Agriculture, horticulture, hydroponics, cooling towers, boiling and steam heating plants, water purification,Pure H2O: Pure water, distilled and de-ionised water, steam cleaning, PCB washing, battery checking High ...
Microprocessor based testers for determination of electrical conductivity ...
Microprocessor based testers for determination of electrical conductivity or Total Dissolved Solids within liquids All units equipped with a custom microprocessor, guaranteeing high accuracy and linearity over the measurement range Automatic calibration function Automatic temperature compensation Primo 2 measures ...
Floating, waterproof, easy to use with replaceable electrodes, ...
Floating, waterproof, easy to use with replaceable electrodes, these meters are a must have piece of measurement equipment The HI-98311 and HI-98312 combine a sleek pocket sized design with accuracy.Featuring a large LCD display enabling users to read pH and ...
The Pro Sens multi function universal meter and ...
The Pro Sens multi function universal meter and controller has an intelligible display and is built in a closed-in tight housing It can be used in many industrial applications as a standalone device or, thanks to its built-on RS-485 Port ...