How do you know which pH sensor is right for you? You’d like to have a sensor that will deliver the highest measurement reliability with the longest lifespan possible; however, the variety of laboratory pH sensors available might be confusing. Hence, before purchasing an industrial pH probe sensor, it is vital to consider your usage and the circumstances the sensor will be subjected to while in operation. With this guide, you may determine which sorts of capabilities will be necessary. Here are a few factors to think about.

Body Composition

The first step in determining the optimal pH probe for an industrial application is to consider the body composition, chemical, temperature, and control.

Sensor Installation

It is critical to comprehend how the sensor will be installed. The two most popular industrial pH probe installation techniques are in-line and submersed. Depending on the setup technique, multiple pH sensor types and accessories may be available for your application. For instance, if you need an in-line pH sensor, a horizontal surface design may be most appropriate for your purpose since the flow over the sensor functions as a self-cleaning mechanism, extending the probe’s lifespan.

Chemical Interaction

When using polymer-bodied electrodes, you should constantly evaluate the compatibility of the sensor body material with any chemicals that may be found in the sample. Polymer body probes are never utilised in liquids with inorganic compounds in general. Moreover, if the sample solution contains extremely corrosive elements, a glass-bodied electrode should be used. This is because glass is a fairly inert material, implying that it resists chemical processes that may damage other substances.

The ideal pH sensor will have a polymer body in situations where the sensor will be operated with a heavy hand or encounter any impact since polymer bodies can withstand more shock than glasses and prevent breaking.

Temperature Adjustment

The pH scale is temperature-dependent. There could be an inaccuracy factor depending on the temperature and pH. If you need very precise pH measurement in high-temperature situations, the optimal pH sensor for your needs will incorporate temperature integration. For this reason, laboratory pH sensors with incorporated temperature sensors are often available. When choosing an ATC probe, you should also evaluate if your pH metre can take a temp component and whether the pH sensor complements the metre.

Connector or Cable Length

This is the diameter between your sensor and your device, which might be a controller, analyser, or transmitter. If the wire length exceeds 8 metres, a pre-amplifier must be installed between the sensor and the controller. A pre-amplifier transforms a pH or ORP sensor’s high impedance mV signal to a reduced resistance signal that can reach 1000 feet.

Furthermore, always ensure that the pH sensor’s connection fits the pH metre. The most popular connection for a pH sensor is a BNC connector; however, there are many additional options. Also, if your toughest industrial pH probe has an embedded temperature sensor, make sure the temp element’s connection is compatible with the pH metre you want to use.

Sealed Electrodes

Sealed pH sensors need less upkeep and are less expensive. On the other hand, sealed designs containing gel reference materials will ultimately decrease or get damaged and must be replaced. Refillable pH sensors contain a resealable hole towards the top of the body, allowing users to replenish the internal fluid solutions when they run out. This increases the sensor’s lifespan and guarantees that readings are accurate for the duration of the sensor’s life.

Some reloadable lab pH sensors will also have a washable junction intended to react fast and precisely to temperature changes. 

Device Suitability

It is essential to determine if the industrial pH probe will be linked to a transmitter, analyser, controller, data logger, PC, PLC, DCS system, or other devices. This is crucial because you need to know what sort of output signal the sensor requires and if it is suitable with the equipment you will be utilising. Moreover, if temperature adjustment is enabled, it is also critical to align the temperature element incorporated in the pH sensor to the temp demand of the device’s front end. 

Automatic Temperature Compensation

Temperature affects pH measurement. Temperature correction is essential for your pH measurement if your industrial application has an excessive and variable temperature range. When determining if an automated temperature compensation (ATC) is required, the targeted pH accuracy, operational temperature range, and pH measuring range should be considered.

Single or Double Junction

A double junction electrode will give further protection against standard contamination if your application includes evaluating materials that may consist of proteins, toxic substances, iodides, sulphides, cyanides, or any other item that may interact with silver or chloride ions. This increases the sensor’s operating life. In more broad applications, single-junction electrodes may be employed.

With the factors stated above to assist you in making the best choice, you are now ready to decide on the ideal industrial pH probe for your specific purposes.