Company History

For more than 100 years DEHN has been serving the electrical industry. From the beginning, protecting buildings and personnel from the effects of direct lightning strikes, to its current business of protecting electrical equipment and systems from the consequences of lightning currents and voltage surges.

As electrical power systems became more complex, the electrical loads, such as process control, computer and telecommunication systems, solid state controllers and relays become more commonplace and sensitive to the aberrations that appear on these power sources, DEHN has continued to improve and develop new products and technologies for maintaining the integrity and reliability of these modern systems. This has lead to DEHN’s leadership role in MOV based TVSS technology and their capability to suppress even lightning rated transients with 10/350 µsec durations.

DEHN currently employs a staff of more than 600 engineers, technicians, craftsman and administrative personnel, and has contracting branches employing another 250 employees, serving in subsidiaries and with partnering companies in more than 50 countries throughout the world including, DEHN Inc. serving the United States market. DEHN heavily invests in its own research and development, as well as contributing and exchanging information with others at international technical conferences and serving on technical Standards committees, to further the knowledge and technology in the fields of lightning protection and transient voltage surge suppression. DEHN manufactures its component products under an ISO 9001 certified Quality System.

DEHN manufactures a full range of Lightning and Surge protection (TVSS) for application on Instrumentation, Measurement and Control and 600 Volt class power systems. Products are configured for various applications including DIN rail mounting for two wire, Ethernet, RS232, coaxial (for RF and video), NPT pipe enclosed assemblies, as well as complete TVSS units built into NEMA rated enclosures for power applications

DEHN devices are rated for 600 Volt class applications and are respectively rated for Protection Categories (per ANSI C62.41-1991) C, B, or A., are compliant to UL 11449 3rd Edition and components have been tested and approved to conform to international standards as stated, and as indicated also bear UL and CE designations.

More about DEHN...A corporate profile..."Your Safety Comes First"



DEHN is an innovative, globally active family-owned electrotechnical company with more than 100 years of experience and tradition.

1910: Registration of an electrical installation business in Nuremberg. Apart from local network construction, construction of overhead lines and installation work on buildings, mounting of lightning protection systems on buildings is an integral part of the business activities.
1918: Very quickly, Hans Dehn finds himself involved in the complex problems surrounding lightning protection. In 1918, he is granted his first patent on this subject.
1921: A subsidiary is set up in Neumarkt, about 45 km from Nuremberg.
1923: Hans Dehn starts to produce lightning protection and earthing components.
1933: The company grows. Hans Dehn transfers a part of the responsibility to his sons Walter and Willy. Both become co-partners and the family-owned company is named DEHN & SÖHNE. In 1941, the youngest son Richard becomes a co-partner.
1939-1945: The Second World War inevitably affects business development. The premises in Nuremberg and Neumarkt are considerably damaged during the war. Highly motivated, the family starts reconstruction.
1945: The starting point for post-war activities in Neumarkt is a warehouse built during the last months of the war in the area where the headquarters are located today.
1948: The decision to build a hot dip galvanising plant paves the way for developing the subsidiary in Neumarkt into a production site.
1952: DEHN presents lightning protection and earthing equipment at the Hanover Fair for the first time.
1952: The increasing market demand requires a further expansion of the production facilities in Neumarkt.
1952: Besides lightning protection and earthing, the company starts to develop earthing and short-circuiting devices, which are an integral part of our safety equipment portfolio today. The patented ball pin decisively influences the state of the art.
1953: Austria becomes the first exporting country.
1954: DEHN is the world's first manufacturer to launch a surge arrester for use in low-voltage installations, the legendary J250.
1956: The KS connector that reliably connects circular conductors to flat profiles is developed.
1958: The separable earth rod, a pioneering innovation, considerably extends the range of earthing components and is in great demand. DEHN becomes well-known in the field of earthing technology.
1960: The family-owned company celebrates its 50th anniversary. On this occasion, a new administration building is constructed in Nuremberg.
1970 – 1980: The company’s surge protection portfolio is continuously amended and extended. New protective devices such as VA 280 and BLITZDUCTOR are developed.
1977: The safety equipment portfolio is considerably extended: Voltage detectors of type PHE and PHG, which are no longer purchased from other manufacturers, but developed in-house, are introduced to the market.
1984: The first lightning current carrying arrester, DEHNventil, enters the market and becomes a synonym worldwide for a new generation of arresters. It allows the company to strengthen its leading position in the sector of surge protection.
1986: The success story of surge protection starts with the introduction of the world’s first arrester with a modular width of 17.5 mm, VM 280.
1988: Foundation of DESITEK A/S in Denmark - the first subsidiary outside Germany.
1991-1998: The company prepares for the future by developing and implementing the master plan DEHN 2000. National and international success requires comprehensive restructuring, reorganisation and reorientation in Neumarkt.
1993: The new energy-coordinated arresters of the Red/Line family for low-voltage consumer‘s installations is launched. Surge protective devices such as DEHNport and DEHNguard start their success story.
1996: The new energy-coordinated arresters of the Yellow/Line family for the protection of data and automation systems are presented. BLITZDUCTOR CT stands as milestone in the development in the field of lightning and surge protection.
1999: For transparency reasons, activities in the field of installation of electrical systems are spun off into a separate subsidiary called DEHN INSTATEC GmbH based in Nuremberg, Neumarkt and Hermsdorf (Germany).
2002: The master plan is continued by moving into new production facilities for surge protective devices.
2003: Completion of and move into a new administration building in Neumarkt.
2003: The HVI conductor stands as milestone in external lightning protection. The separation distance can be easily maintained by using the new high-voltage-resistant down conductor, even in case of challenging architectural design.
2004: 50 years of surge protection by DEHN.
2006: Safe and functional arresters with a unique design. The new Red/Line and Yellow/Line product families are launched.
2007: A three-storey production facility is built to expand the production capacities in Neumarkt.
2008: The new DEHNrecord MCM XT condition monitoring system acts like an early warning system, generating a fault message already in the event of imminent arrester overload.
2009: DEHNguard SCI, a surge protective device for use in PV systems, is introduced to the market. It combines effective surge protection with personal and fire protection.
2010: DEHN celebrates its 100th anniversary. The small electrical installation business became a globally active family-owned company.
2010: We fund an endowed professorship at the Ilmenau University of Technology  to promote fundamental research on modern methods, technologies and materials in the field of lightning and surge protection.
2011: Foundation of our subsidiary DEHN INDIA in Gurgaon (New Delhi).
2012: DEHNvenCI, a coordinated spark-gap-based lightning current and surge arrester with integrated backup fuse, is introduced to the market.
2012: In the field of safety equipment, DEHN presents a new arc-fault-tested protective suit. DEHNcare consists of a safety helmet, protective gloves, trousers as well as jacket or coat.
2012: Spark gap technology and d.c. extinction circuit of the DEHNlimit PV 1000 V2 combined arrester protects PV systems.
2013: Active arc fault protection system DEHNarc protects persons against the effects of arc faults and prevents damage to installations, downtime as well as the resulting costs.
2013: Establishment of three new subsidiaries DEHN PROTECTION SOUTH AFRICA (Pty) Ltd. in Johannesburg, OOO DEHN RUS in Moscow and DEHN PROTECTION MÉXICO, S.A. de C.V. in Mexico City.
2013: The high-voltage-insulated HVI power Conductor is an ideal solution that makes lightning protection even more efficient. It ensures an equivalent separation distance of 90 cm in air.
2013: DEHNconnect DCO SD2, an efficient surge protective device that increases the safety of, for example, automation systems.
2013: DEHNcombo YPV SCI type 1 and 2 combined arrester with SCI technology for PV systems.
2013: DEHNcube YPV SCI the first type 2 d.c. surge arrester for PV systems to be installed outside of enclosures up to IP65 and is thus ideally suited for protecting string inverters.
2014: Change of management: Thomas Dehn retired after more than 33 years as Managing Partner. Besides Dr. Philipp Dehn, who joined the DEHNgroup in 2011 as Managing Partner, and Dr. Peter Zahlmann, Helmut Pusch took over the managerial responsibility.
2014: DEHN opens new logistics and production site in Muehlhausen (near Neumarkt).
2014: The new BLITZDUCTOR SP is a powerful surge arrester which increases safety of data and information technology as well as measuring and control systems.
2014: The DEHNcord type 2 surge arrester reliably protects for example outdoor LED lights from surges caused by lightning interference.
2014: The intelligent type 2 surge arrester DEHNguard SE features an early warning system (Lifetime Indication) which informs the user of an arrester’s end of life at an early stage.
2014: The new DEHNbox TC 180 is ideal for use in modern telecommunication systems (ISDN, analogue telephones, xDSL). Surges are limited to an acceptable level for the connected terminal equipment without interfering with the data signal.
2014: Foundation of a new sales office in Turkey.
2014: The telescopic test joint box from DEHN is a product for easy and proper integration of a test joint in the building insulation, i.e. the thermal insulation composite systems (ETICS).
2014: 200 kA clamps for LPL I and II with a lightning current carrying capability of 200 kA (10/350 µs) withstand maximum loads.
2014: DEHN Test Centre: The newly designed test laboratory generates extremely high lightning currents with a peak value up to 400 kA in the standardised 10/350 μs test wave form.