3EQ product family – surge arresters with silicone housing, composite hollow core design

Siemens 3EQ surge arresters with silicone housing and a composite hollow core design are ideally suited for the reliable protection of:

– Transformers
Circuit breakers
– Generators
– Motors
– Capacitors
– Bushings
– Switchgear

The surge arrester with the composite hollow core design uses silicone and fiberglass-reinforced plastic (FRP) as housing materials. The direct molding of the silicone onto the FRP hollow core ensures reliability, while an excellent special sealing of the flanges at both ends of the surge arrester effectively prevents partial discharges and moisture ingress. This guarantees decades of trouble-free operation.

The combination of silicone rubber and the fiberglass-reinforced hollow core also allows for outstanding mechanical stability.

The surge arrester with the composite hollow core design provides a very high degree of safety: In the event of an overload or the extremely rare case of an arrester short circuit, the arc escapes directly through directional pressure relief devices.


The surge arrester can be oriented to minimize the risk of damage to facilities and injuries to people nearby. Internal parts are not ejected, and the housing does not break.


3EQ surge arresters can be used as station or support insulators. They are ideally suited for areas with the heaviest seismic activity, extremely strong winds and in support functions.