In mobile communications, high availability and reliability of equipment and system technology are critical in both the private and public sectors. When configuring network infrastructure and planning new sites, planners, installers and operators must take lightning and surge protection measures, which are also required from an insurance perspective.

Increasing demand for 5G technology means that we need higher transmission capacities and better network availability. New cell site locations are being developed constantly for this purpose, with existing infrastructure being modified and expanded. These cell sites must obviously be reliable, but the exposed location of mobile radio masts makes them vulnerable to direct lightning strikes, which could cause severe damage to the systems.

They can also be damaged through power surges, which can be caused by nearby lightning strikes, as well as by the current reality in South Africa of the abrupt stops and starts of load shedding. Therefore, a comprehensive lightning and surge protection concept, which provides optimum protection and high system availability, is imperative to protect these costly and sensitive equipment sites.

A lightning protection system provides optimal protection by coordinating both the external and internal lightning protection segments:

• The external lightning protection system consists of an air termination system, down conductor and earth-termination system.
• The internal lightning protection system encompasses lightning equipotential bonding and surge protective devices.

“DEHN has been successfully developing customised products and protection solutions for cell sites for over 25 years,” says Ivan Grobbelaar, Senior Engineer at DEHN Africa. “As an all-in-one supplier, DEHN supports network operators, power supply manufacturers and system technology suppliers, as well as general contractors and service partners.

“DEHN equipment has the capacity to protect all aspects of the cell site, including the antenna, the aviation lights on the tower, the base transceiver station equipment (BTS), the power supply unit, remote radio heads and the telecommunication lines. Products that are used for protecting cell sites include DEHNvap, DEHNsecure, DEHN BLITZDUCTOR and DEHN HVI technology.”

DEHN protection solutions include planning and selection of components for earth termination systems and external lightning protection systems, as well as the use of lightning current and surge arresters in mobile radio stations. Combined lightning current and surge arresters, also referred to as combined arresters, are used to protect the infrastructure in power supply systems.

DEHNvap CSP combined arresters: protection of the base station   

DEHNvap CSP (cell site protection) combined arresters are specifically designed for mobile communication applications. When using combined arresters, energy coordination with system and equipment technology is an important criterion. The DEHNvap CSP arresters are extensively tested to ensure their coordination with the integrated input circuits of power supply units.

DEHNsecure surge arresters: protection of the power supply unit and remote radio heads

Mobile radio systems rely on remote radio heads. The high-frequency signal is directly generated at the antenna and is then transmitted. Optical fibre cables, which have significantly higher transmission ranges than conventional coaxial cables, transmit data between the remote radio heads and the base station. The remote radio heads are supplied by a separate 48 V dc line. Operators as well as power supply manufacturers rely on DEHNsecure dc lightning current arresters.

DEHN BLITZDUCTOR: protection of telecommunication lines

Land-line connections by means of copper cables or microwave links are used to connect base stations to higher-level switching technology. In the case of land-line connections, partial lightning currents can flow through the telecommunication lines in case of a direct lightning strike in the antenna system. BLITZDUCTOR XT combined arresters provide reliable protection.

DEHN HVI conductors: protection of the radio antenna

The lightning current-carrying core of DEHN HVI conductors is coated with insulating material in such a way that the required separation distance to other conductive structural features or electric lines and pipes is easily maintained and flexible. Installation takes place directly next to conductive structural parts, and the modular components mean that mounting is safe, quick and easy.

“DEHN Africa provides information and services across the various aspects of the network industry. As we in South Africa anticipate the ongoing reality of load-shedding for at least another couple of years, DEHN’s expertise will also allow telecom businesses to protect their investments from the threat of surges as well as direct and indirect lightning strikes,” concludes Grobbelaar.