SIEMENS 3EJ SILICONE RUBBER SURGE ARRESTERS WITH CAGE DESIGN™- MEDIUM VOLTAGE SURGE ARRESTORS FOR DISTRIBUTION NETWORKS .

Siemens 3EJ silicone surge arresters with cage design are ideally suited for reliable protection against overvoltages in medium-voltage distribution networks.

Siemens 3EJ cage design surge arresters are ideally suited to provide reliable protection for:

• Generators
• Motors
• Arc furnaces
• Dry-type transformers
• Airfield lighting systems
• Cable sheathing
• Capacitors and capacitor banks
• Converters for drives

The cage, made of fiberglass-reinforced plastic (FRP) rods, provides a rigid, reinforced structure ensuring high mechanical strength.

The silicone rubber housing is directly molded onto the metal oxide (MO) blocks and the surrounding cage made of FRP rods. This creates a reliable seal that prevents moisture ingress and partial discharges.

The MO resistors are not surrounded by a rigid mechanical coating, which is why no critical increases in pressure can occur in the surge arrester in the extremely rare event of an overload. The arc can escape directly through the soft silicone housing without damaging the mechanical structure. No internal parts are ejected in the process. The innovative Siemens cage design is very secure.

The 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 3EJ surge arresters.

3EJ SILICONE SURGE ARRESTERS TYPES:

Siemens offers five product types for applications with high energy absorption capacities that vary in terms of the protection level: 

• 3EJ2 – for rated voltages up to 54 kV, medium energy absorption capability
• 3EJ3 – for rated voltages up to 54 kV, high energy absorption capability
• 3EJ4 – for rated voltages up to 54 kV, very high energy absorption capability
• 3EJ0 – for rated voltages up to 15 kV, very low protection level, for protection against overvoltages
• 3EJ9 – for rated voltages up to 15 kV, very low residual voltage, for protection against overvoltages

The proven type 3EJ4 surge arrester is also available for indoor use. The 3EJ4 surge arrester for indoor use is a cage design surge arrester that offers the same features as the version for outdoor use.

The 3EJ0 and 3EJ9 surge arresters are optimized with an extremely low protection level for protection against overvoltages. The type 3EJ0 is used in cable networks with up to 15 kV. Type 3EJ9 surge arresters should be used for power plants and extensive cable networks. These have a higher energy absorption capacity and a better protection level.

Siemens Transmission Products – Leader in innovations with comprehensive, connective and sustainable portfolio

Transmission products play a vital role in the energy value chain. Siemens Transmission Products provides all key elements including power transformers and distribution transformers as well as gas-insulated and air-insulated switchgear and components. Products are offered individually, bundled or with related engineering upgrade to systems. Our products offer low life cycle costs with maximum availability, highest efficiency and short commissioning times.

We are driving technology innovations not only regarding the performance of transmission products but also in the area of sustainability and eco efficiency. By merging physics and data we enable new products and applications: Sensformer® and Sensgear®. With our global factory network and leading innovations we provide the highest level of quality and reliability to our customers: TSOs, DSOs, power producers, EPCs and industrial companies.