Electricity + Control August 2017

ELECTRICAL PROTECTION + SAFETY

Figure 1: High safety for persons and the environment – ensured by a comprehensive surge protection with minimal space requirements.

From the Sensor to the Controller Reliable Signal Transmission in Confined Spaces

Dipl.-Ing. Ralf Hausmann, Phoenix Contact GmbH & Co. KG, Blomberg

A lightning and surge protec- tion concept is essential in large water and wastewater treatment systems−numer- ous manufacturers offer MCR surge protective devices for this. Most of these protective devices, however, do not feature a status indicator. The solution presented in this arti- cle – indicates an overload on the contactor module, and can be queried by the control cen- tre via the easily installed field telecommunications function. In this way, a surge protection concept can be implemented in the most confined spaces with protective devices featuring overall widths of 3,5 mm to 6 mm. Thanks to the multistage protective circuit, the three most important performance requirements − category D1, C2 and C1 − of the surge protection standard EN 61643-21 [4] are fulfilled.

The world’s narrowest surge protection for Measurement, Control and Regulation (MCR) technology recently launched.

T he needs of system operators in the water and wastewater industry have changed dras- tically – there is a trend for higher packing density in the control cabinet and consequently ever narrower components. With ‘Termitrab com- plete’, Phoenix Contact has launched the world’s narrowest surge protection for MCR technology – the narrowest devices are just 3,5 mm wide (see Figure 1 ). It is a characteristic of the water and waste- water treatment industry to have numerous net- worked processes − between field level, man- agement level, and subsections that are usually far apart. The requirements on planners, install- ers, and operators of the systems are increasing steadily. Failsafe concepts are becoming more important due to the increasing implementation

of electromechanical and electronic components, systems and solutions, as well as the networking between them. Megatrends in the market Overvoltage concepts play an important role. Fur- ther requirements on critical infrastructure have also developed due to the IT security law passed after concerns by the Federal Office for Security in Information Technology. Two major factors are at play: High system availability and the resulting security of supply for the population. As in other infrastructure fields, the trend to- wards implementing ever smaller and more com- pact components is also quite noticeable in the field of water and wastewater treatment. To opti- mise the costs of overall control cabinet manufac-

14 Electricity + Control

AUGUST 2017