A private water company formed in 1853 to provide water to the inhabitants of the Black Country, South Staffordshire Water PLC supplies a population of nearly 1.25 million, over an area of almost 1,490km2.
Operating 24 hours a day, the water company traps the rain that falls, controls the amount of water taken from rivers and underground aquifers, treats the water so it is safe to drink and then transports a constant supply to homes and businesses alike.
pH monitoring is a critical process in water treatment in order to maintain water quality. Identifying the need to replace existing pH monitors due to the failing performance of ageing equipment, South Staffordshire Water PLC invited manufacturers of pH sensors to participate in field trials at their main site on the River Severn at Hampton Loade, near Bridgnorth.
The trials were carried out simultaneously with three major pH monitoring manufacturers, each setting their respective instruments up to analyse the same chlorinated water within a contact tank over a two-month period. Laboratory analysis was undertaken several times daily by the site chemist to provide a comparison to the instrumentation readings. These readings were recorded, together with any instrument failures, as evidence to support the decision regarding which manufacturer's product should be recommended.
From these trials it was clear that the Endress+Hauser Memosens digital pH monitoring unit gave the most consistently accurate measurement with the minimum of manual intervention. This, together with its superior 'whole life' cost of ownership, put it ahead of the rest. Due to these findings, personnel on site at Hampton Loade Treatment Works recommended the procurement of 14 units.
Memosens is a patented technology for inductive digital transmission of pH measurement. This system provides an interference-free measurement between the transmitter and sensor, with complete elimination of moisture ingress and problems caused by dirt. What's more, the Memocal T calibration unit is now also being utilised to measure pH grab samples which had historically been tested separately in the laboratory. Sensors can be pre-calibrated and installed on demand, saving both time and money through reduced downtime gained by simple sensor exchange.

Memosens has enabled South Staffordshire Water PLC to obtain accurate and reliable pH measurement with the added benefits of simple calibration, ease of transmitter operation and simple maintenance. As a result, a further order has been placed for four more units, thereby standardising all the pH units at Hampton Loade Treatment Works, with a view to replacing any future pH units with Endress+Hauser's Memosens digital pH sensors.
A technical representative at South Staffordshire Water PLC remarked: "The thing that stood out for me was the simplicity of it all - Endress+Hauser made it so easy. The probes are pre-calibrated so that they can be installed and in operation from day one. And it doesn't end there, Memosens is designed so that sensors can be calibrated onsite, saving us time and money."