WHAT IS A pH METER?
pH meters are volt meters that measure the electrical potential produced by a pH probe. It is used to measure the pH level (the acidity or alkalinity) in a liquid. A pH meter is made up of a pH electrode which is connected to an electronic meter that measures and displays the pH reading.

A standard pH scale is from 0 to 14. An extended range is used in applications requiring a base acid that falls outside the standard pH scale of 0 to 14, and can be either a negative reading such as -2 or as high as +20.

pH meters can be single-parameter to measure only pH, or as multi-parameter measuring conductivity, ISE, TDS, salinity, humidity, temperature, LogR and/or dissolved oxygen.

3 TYPES OF pH METERS:

• Pen-style: most basic form of pH meter. Shaped like a large pen and is quick and easy to use. Ideal for on-the-go pH testing for both home and commercial use.
• Portable handheld: ergonomic, steady and versatile meter. Ideal for taking readings in the field. Much larger selection available — choose from a range of styles, designs and features.
• Benchtop: generally the most precise, least mobile and most expensive. Offers the greatest versatility. Depending on the model, they can provide the option to add built-in printers, data loggers, probe arms and accessories.

ELECTRODES:

• There is a wide variety of electrodes available for every kind of application and industry. Choosing the appropriate electrode for your application can be just as important as choosing the correct pH meter.
• Electrode styles include standard, semi-micro (sample sizes >200µL), micro (sample sizes >0.5µL), rugged bulb (extra durable glass), spear tip (for piercing solid or semi-solid samples) and flat surface tip (for measuring solid surfaces or gel samples and measuring small sample volumes).
• Electrodes should never be stored dry. They need to be stored in electrode storage solution at all times when not in use. If left to dry out, the electrode will not work properly.
• Electrodes have a typical lifespan of 2-3 years if it is properly cared for.

WHAT TO LOOK FOR:
Resolution: choose the resolution (from 0 to 3 decimal places) that is appropriate for your application.
Accuracy: choose a meter that has an acceptable accuracy for your application.
Automatic buffer recognition for calibration.
Automatic temperature compensation (ATC).
Intuitive operation.
Expandability.
Data storage.