Innovative solution ensures alarm connectivity at Dutch water plants

The Dutch government has set the goal of acquiring a leading position in Europe in the development of the electronic superhighways. As such it is modernizing its entire communications infrastructure so that it has capabilities for 5G, fiber, mobile, digital, VOIP (voice over internet protocol) etc. right across the country.

Context and challenge

The phasing out of older technologies has given rise to some issues. For instance, many water treatment plants use old-fashioned, but well proven and reliable analog telephone lines, to connect the alarm functions of plant SCADA (supervisory control and data acquisition) systems, with pagers carried by site engineers and managers. But, effective from September 2019, these telephones lines are being phased out, so there is a need to find a replacement technology.

The obvious answer would appear to be based on the use of modern cellular connections to provide a solution based on SMS text messaging. However, survey after survey revealed that cellular coverage is either not available or of very poor quality across many of the country’s water treatment plants.In an attempt to find the best possible solution, several of the Dutch water utility companies turned to control engineering company Moekotte BV.

Moekotte, leader in the field of industrial automation, has engineers translate complicated technology into practical and effective solutions to real world requirements. They are always monitoring new developments in control technology and start every project by taking the time to fully understand the clients’ current and likely future needs. Various solutions are identified, costed and discussed with the client, to ensure the optimum result is identified before detailed design and installation begin.

The solution

With analog telephone lines being phased out across the country, a solution using Ewon Flexy was developed so that pagers could still be used at waterworks and other sites where cellular connections were weak.

Moekotte BV

To make the project succeed at the water plant, a few objectives were crucial. The first objective was to minimize interference in the daily plant operation. Also, the existing SCADA system with its connectivity and communications needed to remain or improve. Next to that, the use of pagers is mandatory in means of instantly alert personnel in case of alarms. As a part of this, the alarms need to be sent to several people at the same time. The last demand was that the pagers need to be able to pick up other messages as well as alarms.

Naturally there was a great emphasis on developing a cost effective solution, as well as improving flexibility and capability. After considering all the issues, Moekotte suggested a solution based on the Ewon Flexy 205 made by HMS Networks. Incoming alarms nowadays will be sent over the internet using the SOAP protocol (Simple Object Access Protocol), instead of the analogue telephone lines. The Ewon Flexy 205 makes it possible to run a custom built script which converts incoming OPC UA messages towards the outgoing SOAP protocol. These SOAP messages can be received by the pagers.

Benefits for the Dutch water utilities

• Minimal intrusion on daily operational processes.
• Communication and connectivity are maintained as before.
• No major changes to the SCADA system were needed.
• The existing pagers are still in use for informing personnel of critical alarms.
• Provides a scalable solution, allowing deployment on other installations of the Dutch Water Utilities.