Electricity and Control October 2022

SAFETY OF PLANT, EQUIPMENT + PEOPLE

Ensuring safety and availability in telecoms systems Marcus Denker, Telecommunications Application Specialist, Business Unit Trabtech, Phoenix Contact GmbH & Co. KG, Blomberg, Germany Oliver Tananow, Senior Specialist Electrical Engineering Core Site, Telefónica Deutschland GmbH & Co. OHG Robert Krüger, Senior Specialist IT Core Site, Telefónica Deutschland GmbH & Co. OHG State-of-the art communication technology places high demands on reliability and availability. Looking to the future in this regard, network operatorTelefónica Deutschland / O 2 is equipping its systems and digitalising its locations accordingly. An all-encompassing lightning and surge protection concept, plus monitoring, control, and automation of key system parameters at all system-related locations play an important role.With ImpulseCheck, the digital assistance system from Phoenix Contact, previously unmonitored system parameters are transparent and can be processed further.

Marcus Denker, Phoenix Contact.

Oliver Tananow, Telefónica Deutschland.

Prioritising system availability Telefónica Deutschland is one of the largest telecommuni cations network operators in Germany. “In view of the current requirements associated with considerations such as digital Industry 4.0 and production in real time, cellular communication is becoming a particularly significant aspect of critical infrastructure. What’s important here is the permanently high availability of key central system areas, which we are constantly reviewing and steadily increasing with the help of new technologies,” says Oliver Tananow, who is responsible for system planning and implementation at Telefónica Deutschland. The comprehensive use of lightning and surge protection components is a key building block for increasing availability. When creating a lightning protection concept, it is essential to safeguard the power supply. Power supply failure caused by transient events can be avoided through the consistent use of lightning and surge protective devices. Surge protection and lightning protection zones Protecting a telecommunications system (whether a cellular system or data centre) from the effects of lightning strikes

and overvoltages requires multiple, coordinated protective measures and devices. It is important to establish a comprehensive, coordinated system of lightning and surge protective devices (SPDs). A coordinated SPD system is a multi-stage system of lightning and surge protective devices. The installation locations of SPDs within a system are determined using a lightning protection zone concept based on lightning protection standard IEC 62305-4. The system is divided into lightning protection zones (LPZ) from the outside to the inside, with decreasing lightning protection levels. In this context, the following key areas requiring protection have been identified and equipped with lightning and surge protective devices. ƒ Grid feed-in point for power supply: The transfer point from the power provider to the data centre is the first critical interface where high lightning currents need to be taken into consideration. A high performance type 1+2 combined lightning current and surge arrester provides the necessary protection here. ƒ AC main distribution: The cables from the feed-in and the emergency power supply come together in the main distribution. As light ning currents and overvoltages can also be expected in this part of the system, a compact type 1+2 device combination provides the required lightning and surge protection. ƒ Dc power supply: Due to the physical proximity to the ac main distribution, further couplings can be prevented in this area, which is why additional SPDs did not need to be used here. ƒ Emergency power supply: If, contrary to expectations, the main power supply suffers a failure, the emergency power supply is activated. First, a large battery storage system bridges the time until the permanently installed diesel generator has started up and reached its stable operating point. In this particular application scenario, although lightning

Robert Krüger, Telefónica Deutschland.

Requirements relating to Industry 4.0 and the need for real-time communications make cellular communication an increasingly important aspect of critical infrastructure.

26 Electricity + Control OCTOBER 2022