Motorized disconnect switch 3DN4

compactverticalindustrial

Overview
Learn about Siemens Energy high-voltage disconnectors and earthing switches designed for industrial and utility applications. The range covers wide voltage levels and robust configurations for indoor and outdoor installations, with technical variants referenced up to 1200 kV in detailed overviews.

Production and quality
Siemens Energy applies standardized production processes, continuous product development and certified quality management to ensure consistent performance. A global manufacturing network reduces lead times and transport footprint while supporting local delivery and service.

Main features

• Voltage range: typical values 36 kV–800 kV; technical overviews indicate up to 1200 kV
• Rated current up to 5000 A; rated short-circuit currents up to 80 kA (often specified for 1 s)
• Short-circuit ratings are maximum values and require verification for specific applications
• Materials and constructions suitable for seismic areas and extreme climates
• Variants for indoor and outdoor use, including coastal and saline-fog environments
• Designed to meet switching capacity requirements, including commutating currents and electromagnetic/electrostatic coupling considerations

Advantages

• Maintenance-minimised contact systems; some variants operate without mechanical springs
• Efficient cost-to-performance balance for utility and industrial projects
• Operational reliability in wide temperature ranges, icing conditions and seismic zones
• Type-tested to IEC 62271-102 and tested against IEC, ANSI, GOST R and GB standards
• Quality management certified to DIN EN ISO 9001
• Routine-tested and pre-adjusted assemblies simplify installation and commissioning
• Long-term technical support and service options

Variations
3DN1 center break disconnectors

• Two rotating insulators mounted on an integrated base frame
• Current path opens to the side, enabling larger phase distances in parallel layouts
• Versatile arrangements: parallel, diagonal or in-line installations
• Integrated base frame adaptable to support structures
• Available in multiple colors and configurations
• Maintenance-minimised contact system
• Extended RIV limits per voltage level to reduce electromagnetic interference

3DN2 double side break disconnectors

• Three supporting insulators with a rotating centre insulator carrying the current path
• Outer supports hold fixed contacts; two open separation sections
• Compact, stable design enabling high mechanical tensile loads
• Compatible with surge arresters and additional accessories
• Available with self-interlocking mechanisms and various color options
• Maintenance-minimised contact system

3DN3 pantograph disconnectors

• Space-efficient design with scissors-type busbar connection
• Vertical disconnection and busbar connection options
• Suitable for diagonal or parallel arrangements and for flexible or rigid busbar systems
• Compact, mechanically and thermally robust design
• Self-interlocking prevents unintended opening during short-circuit events

3DN4 vertical break disconnectors

• Current path opens vertically to allow small phase distances
• Combined vertical swinging and rotation about a longitudinal axis
• Large distance between supporting and rotating insulators for high dielectric strength in saline environments
• Delivered as finished assemblies to reduce installation and commissioning time
• Available with self-interlocking and multiple color options

Contact systems
Contact systems are engineered for dynamic and thermal stability and long operational life:

• Contact force increases under short-circuit conditions
• High stability for leakage and switching currents
• Optimized for silver-plated contacts where specified
• Lubrication-free and long-term maintenance-minimised solutions
• Proven operational experience with designs based on long-term field service

Modular design
Device families share common basic components to simplify engineering and spare parts management:

• Current path
• Contact system (except pantographs)
• Supporting insulator
• Rotating insulator
• Base frame
• Connecting rods (except center-break)
• Drive

Drive systems
Available drives support reliable operation and straightforward commissioning:

• 3DV8 motor drive: integrated motor and gearbox with electrical equipment and auxiliary switch; low-noise, maintenance-minimised transmission
• 3DV4 manual drive: lockable hand-lever for safe maintenance and operations
• 3DV1 control unit: signal collection and centralization for single-pole or combined disconnector/earthing mechanisms

Technical specifications

• Voltage range: typical 36 kV–800 kV; technical overviews reference up to 1200 kV
• Rated current: up to 5000 A
• Rated short-circuit current: up to 80 kA (often specified for 1 s; verify per application)
• Ambient temperature range: -60 °C to +55 °C (reference in technical overview)
• Standards: type-tested to IEC 62271-102; compatible with IEC, ANSI, GOST R and GB
• Quality: DIN EN ISO 9001 certified quality management
• Design options: indoor/outdoor variants, seismic-resistant materials, self-interlocking options, delivered as routine-tested pre-adjusted assemblies