Glossary

Short Circuit Interruption

Direct currents (d.c.) flow on the generator side of a PV system. The surge protective devices used on the generator side can be overloaded due to different scenarios (e.g. impulse load, insulation faults) and must not endanger the PV system. However, insufficient d.c. disconnection capability in a PV system may cause fire. Conventional surge arresters only feature a disconnector in the form of a simple break contact mechanism which is typically used for a.c. devices. Due to the lacking zero crossing of the d.c. source, 
a d.c. arc may persist and cause fire. The SCI technology patented by DEHN + SÖHNE with active arc extinction is an ideal solution. In case of overload, a contact is opened and a shortcircuit is generated (Short Circuit). Thus, a possible switching arc is actively, quickly and safely extinguished. The PV fuse integrated in the short-circuit path immediately trips after the arc has been extinguished and ensures safe electrical isolation (Interruption). Thus, all PV arresters from DEHN + SÖHNE combine surge protection, fire protection and personal protection in a single device

Sub-Distribution Board

Smoke Detection System

Service Entrance Box

Safety Extra-Low Voltage

Switching Electromagnetic Pulse

Resistance in the direction of the signal flow between the input and output of an arrester.

Relation of the power fed into a coaxial cable to the power radiated by the cable through the phase conductor.

Maximum uninfluenced short-circuit current which the SPD, alone or in conjunction with its disconnection devices, is able to withstand.

The short-circuit withstand capability is the value of the prospective power-frequency short-circuit current handled by the surge protective device when the relevant maximum backup fuse is connected upstream.

Surge Protective Device

Surge Protection Measure

Security Services

Stainless Steel

Surge protective devices mainly consist of voltage-dependent resistors (varistors, suppressor diodes) and / or spark gaps (discharge paths). Surge protective devices are used to protect other electrical equipment and installations against inadmissibly high surges and / or to establish equipotential bonding.