Motorized isolator switch 3DN1

manualhigh-voltage3-pole

Overview
Siemens Energy high-voltage disconnectors and earthing switches provide visible isolation and safe de-energization across a wide range of voltages and environments. They combine proven contact and drive concepts with modular engineering for substations, overhead lines and critical power-transmission applications.

Main features

• Voltage range: 36 kV to 800 kV (main range on page)
• Rated current up to 5000 A; short-circuit capability examples up to 80 kA (1 s)
• Durable materials and designs for seismic areas and harsh climates
• Suitable for indoor and outdoor installation, including coastal and high ice-risk regions
• Designed to meet switching capacity requirements including commutating currents and electromagnetic/electrostatic couplings

Advantages

• Maintenance-free contact concepts (classic designs without spring elements)
• Type-tested according to IEC 62271-102 and tested to other national standards where required
• Quality system certified to DIN EN ISO 9001
• Routine-tested and pre-adjusted assemblies to simplify erection and commissioning
• Proven long-term operation and available life-time technical support

Disconnectors and earthing switches variations

• 3DN1 center break disconnectors: Worldwide common type with two rotating insulators that open/close contacts sideways; integrated base frame, large phase distance in parallel arrangements, maintenance-free contact system and extended RIV limits to reduce interference.
• 3DN2 double side break disconnectors: For limited phase space or where vertical opening is not possible; three supporting insulators, compact and stable design for high mechanical loads, optional self-interlocking and surge arrester compatibility.
• 3DN3 pantograph disconnectors: Minimal mounting space with scissors-like busbar connection; vertical disconnection, suitable for flexible or rigid busbars, compact and self-interlocking design.
• 3DN4 vertical break disconnectors: Vertical current path opening enabling small phase distances; combined swinging and rotary movement for high dielectric strength in saline fog; delivered as finished assemblies for reduced installation time.

Modular design
All device types share the same basic components to simplify engineering, spare parts and logistics.

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

Contact systems

• Increased contact force under short-circuit conditions
• High dynamic and thermal stability in leakage-current scenarios
• Optimised for silver plating and lubrication-free operation
• Maintenance-free long-term performance with proven designs (+40 years operating experience)

Drive systems

• Pre-finished, pre-adjusted assemblies for simplified installation and commissioning
• Robust housings (e.g. stainless steel, IP54) and IEC-tested auxiliary switches
• Options: 3DV8 motor drive (motor-integrated transmission, low noise), 3DV4 manual drive (lockable lever for safe maintenance), 3DV1 control unit (centralised control/signalling)
• Compliance with international standards (IEC, GOST R, GB) and anti-condensation/heater options

Applications
Designed for AIS and GIS substations, overhead lines and major transmission projects where visible isolation, safe de-energization and reliable switching are required, including operation in severe climates.

Technical specifications

• Voltage ranges: 36 kV to 800 kV (main range) — referenced ranges up to 40.5 kV–1200 kV in supplemental material
• Rated current: up to 5000 A
• Rated short-circuit current: examples up to 80 kA (1 s)
• Ambient temperature examples: -60 °C to +55 °C
• Type-tested to IEC 62271-102; tested to ANSI, GOST R, GB where applicable
• Quality management: DIN EN ISO 9001
• Delivered as routine-tested, pre-adjusted assemblies to reduce erection and commissioning time