Active arc fault protection by means of DEHNarc

The fast and coordinated interaction of the components of the DEHNarc arc fault protection system, consisting of a visual detection system, control unit and short-circuiter unit, ensures minimal disconnection times in low-voltage switchgear installations when arc faults occur. This preventive measure protects persons against the effects of arc faults and prevents damage to installations, downtime as well as the resulting costs.

The protective effect of personal protective equipment (passive arc fault protection) with regard to the thermal effects of arc faults depends on the intensity of the arc energy and the associated incident energy and is thus limited. Therefore, active arc fault protection systems are a useful addition to this basic protection. These systems can already be fixed at the planning stage of the installation. The DEHNarc system is also suitable for mobile use in open low-voltage distribution boards. Existing installations and systems can be easily and quickly equipped with DEHNarc.


The efficiency of the protection system depends on the limitation of the incident energy of the arc. The extremely short disconnection times of the DEHNarc protection system significantly reduce the fatal consequences of an arc fault. To this end, it is essential that the arc fault current is quickly conducted to a short-circuited parallel branch, the so-called short-circuiter. The effective interaction between the arc detection system and short-circuiter ensures that the arc fault is extinguished after some milliseconds before the overcurrent protective device is tripped. The arc duration is significantly reduced, thus considerably reducing the arc energy. As a result, persons are protected from the effects of an arc fault and the availability of the installation is increased (IEC 60364-4-42).

Safety devices and equipment from DEHN are manufactured and tested in compliance with applicable standards. DEHN is also a reliable partner for maintenance tests on earthing and short-circuiting devices, voltage detectors, switching sticks, fuse tongs, insulating sticks and earthing sticks.


DEHN + SÖHNE GmbH + Co. KG.Public RelationsAdvertising Department
Postfach 1640
D-92306 Neumarkt

Phone: +49 9181 906 0
Fax: +49 9181 906 1100

Petra Raab

Phone: +49 9181 906 1426
Fax: +49 9181 906 55 1426

Werner Meier

Phone: +49 9181 906 1123
Fax: +49 9181 906 1478