Medium-voltage surge arrester 3EK8 series

class Ifor electrical installationsfor electrical networks

Siemens 3EK8 silicone rubber surge arresters with wrap design effectively protect medium-voltage distribution networks from overvoltage. Siemens 3EK8 wrap design surge arresters are ideally suited to provide reliable protection for: •Transformers •Circuit breakers •Medium-voltage switchgear •Medium-voltage distribution networks The silicone rubber housing is directly molded onto the metal oxide (MO) blocks. This creates a reliable seal that prevents moisture ingress and partial discharges. In the extremely rare event of an overload, arcing cannot result in a buildup of critical internal pressure, since the MO resistors are not enclosed in a sealed rigid mechanical shell. The arc can escape directly through the fiberglass wrap and the soft silicone housing without damaging the mechanical structure. No internal parts are ejected in the process. High-temperature vulcanized (HTV) silicone rubber is highly hydrophobic. This keeps any conductive moisture from forming on the surface, and dirt deposits are rendered harmless as a result of the hydrophobic transfer. Silicone is highly fire-retardant and self-extinguishing in the event of fire. These properties ensure the reliable, maintenance-free operation of 3EK8 surge arresters. 3EK8 surge arresters can be delivered with the same accessories like 3EK7 surge arresters.