pH/ORP Sensors

There are so many different pH and ORP probes on the market, each with their own features and advantages. While it’s necessary to get a specific probe with specific features for some applications, the reality is that the majority of process pH and ORP measurements can be made with just a few different types of probe. Here at South Fork Instruments, we have distilled down our offering to just a few different models that will cover the vast majority of inline process measurements. Having a limited set of probes that adequately and reliably covers so many applications makes for lower maintenance costs and reduced spare parts holding.

We’ve also taken advantage of the latest Memosens™ digital technology, bringing even more cost savings to users through easier handling, more accurate calibration and expanded data and diagnostics availability. For users that haven’t upgraded to Memosens™, we have analog versions that will connect to just about any analog pH transmitter/analyzer in the field.

For “difficult” applications, REFEX pH and ORP probes are available. The REFEX reference is a patented, highly stable, non-porous polymeric interface. The active reference area comprises the entirety of the outside surface of the electrode and this extremely large contact area means that electrode performance is supremely resistant to coating. Drift and premature “death” from the poisoning effects of substances such as cyanide, ammonia and sulfides are eliminated because the polymeric reference material is conductive to ions but being non-porous, does not allow process material to diffuse into the cell; the reference operates electrically, but electrolyte and process fluids are not exchanged. Highly resistant to poisoning and electrode dilution, REFEX sensors can be used with great success in applications with oily/fatty process water/wastewater as they are largely impervious to the greater pollution loads these applications carry.

Probes are available in both industry standard 12mm diameter and large volume NPT threaded packages. A variety of pH glass types are available to suit various application needs and available reference junctions include PTFE, Ceramic, and polymeric materials. Additional options of ion trap or salt reserve are available to combat poisoning and electrolyte dilution. The high reliability of our pH/ORP sensor range ensures that maintenance requirements and cost of ownership are kept very low.