Gas-insulated switchgear

Gas-insulated switchgear

The Siemens Energy range of gas-insulated switchgear (GIS), for rated voltages from 72.5 kV up to 550 kV, is an extremely successful product concept. Since its introduction back in 1968, Siemens Energy has installed switch fields in all climatic zones of the earth, recording over 420,000 years of operation since. Our over 45 years of experience with SF6 technology together with continuous development based on the latest research findings guarantees demand-oriented technology and the highest possible quality and cost-effectiveness. Their compact design allow their use in the most confined spaces, whether in the basement of a high-rise building, in a department store, in an industrial plant, on the first floor of an old historic building or in a mobile container.

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With our Blue portfolio of innovative switchgear technology, you can reduce your global warming impact to zero. That means zero F-gases, zero greenhouse gas emissions and zero harm to the environment. 

NEW: Low Power Instrument Transformer (LPIT)

Siemens Energy LPITs are innovative voltage and current transformers providing a safe, reliable and standardized solution for measurement and protection applications in GIS. Without saturation nor ferro-resonance phenomena, our LPIT provides a digital signal output signal acc. ​to IEC 61850-9-2 or can be plugged directly into a Siemens SIPROTEC 5 device.​​ The LPIT combines a Low Power Voltage Transformer (LPVT) and a Low Power Current Transformer (LPCT) fully compliant to the IEC 61869 series of standards.​​ The measurement is based on Rogowski coils for current and capacitive voltage sensors. Both sensors are integrated in the same GIS cast resin bushing. ​


  • Smaller size and weight of the GIS due to smaller dimensions of the sensors
  • Easy connection and lower cabling and wiring effort
  • High reliability and long lifetime expectance due to  robust cast resin design
  • Less insulation gas in the switchgear
  • Excellent overvoltage performance: no need for disconnection during GIS or HV cable tests 
  • No hazardous overvoltage at open terminals
  • A single LPIT covers all protection and metering requirements and thanks to its linearity also a wide range of primary currents and voltages, simplifying stock management, engineering and logistics.
  • Flexible definition and modification of the settings for rated primary current and voltage at any phase of the project and afterwards
Product overview

Overview of our technology and models

We offer a wide range of gas- and vacuum-insulated switchgear for all types of requirements – reliable, cost-effective and trendsetting.

Main features

  • Modular structure
  • Safe encapsulation
  • High degree of gas tightness
  • Good accessibility and ergonomics
  • Environmentally compatible design

In addition to gas-insulated switchgear, Siemens Energy also supplies gas-insulated transmission lines (GIL) for transmitting high capacities of power over long distances.


  • Very flexible switchgear designs and problem-free extension
  • Economic efficiency
  • High reliability
  • Customer-oriented support
  • Long service life
  • Low life cycle and maintenance costs
  • High availability
  • Safe operation even under extreme environmental conditions

Our Blue GIS products

Enabling higher voltages within wind turbines

Increased environmental awareness and improved resource efficiency are essential in today’s world. Offshore wind power is making a major contribution to meeting these challenges. Increasing power demand requires a new generation of wind power plants equipped with innovative technologies. One core aspect: Due to increased wind turbine power, there is a movement to high voltage within the wind turbine network to decrease the current and therefore the cable losses. This is where compact, environmentally friendly high-voltage switchgear can make an optimal contribution.


Main features:

  • Worldwide leading F-gas-free environmentally friendly technology
  • Innovative clean air insulation medium
  • Proven vacuum interrupter technology
  • Compact GIS design for offshore wind turbine installations
  • Optimal installation, commissioning and service concept
  • Completely factory assembled and tested switchgear
  • Shipped in single transport unit, ready for cable connection
  • Same dimensions for all typical switchgear configurations
  • One gas compartment for circuit breaker, disconnectors and earthing switches
  • Component design based on well-proven technology
  • Cable terminals for T-connectors
  • Maintenance-free operation
  • Safe and easy handling

Vacuum interrupting technology and clean air insulation for a neutral carbon footprint

Environmental awareness and increased resource efficiency require new technologies. This poses new challenges for the electrical industry and creates a demand for products that are environmental friendly. Siemens Energy has developed innovative solutions using alternative technologies that enable the F-gas-free, easy and secure transmission of electrical power. The new 8VN1 Blue GIS up to 145 kV combines proven vacuum-switching technology with the advantages of clean air as an insulation medium.


Main features:

  • World's leading F-gas-free, environmentally friendly, and future-proof technology
  • Zero Global Warming Potential (GWP)
  • Zero impact on health and safety (non-toxic, non-hazardous)
  • In compliance with future norms and standards for environmentally friendly insulation mediums
  • Proven vacuum interrupter technology
  • Maintenance-free operation
  • Safe and easy handling, no special safety precautions or training required
  • High operational safety
  • Low operational costs throughout the entire lifecycle

Vacuum interrupters

Siemens Energy has over 40 years of experience in producing medium-voltage vacuum interrupters and delivered more than 5 million units.
Siemens Energy introduced this proven technology to high-voltage power networks in 2010. The hermetically sealed vacuum interrupters are reliable and maintenance free thanks to its “sealed for life” technology.


High performance

  • Suitable for frequent switching: high number of short circuit interruptions with excellent switching features over the entire service life of the vacuum interrupter

Perfect for low temperatures

  • Switch medium does not liquefy

Zero CO2e (equivalent) emissions

  • switch medium (vacuum) with greenhouse potential (GWP) = 0;
  • No CO2e emissions during operation, maintenance or recycling
  • No emission or emission compensation costs throughout the service life

Videos on our gas-insulated switchgear

Our 8D GIS products

8DN8 gas-insulated switchgear up to 170 kV

Our type series 8DN8 switchgear is one of the most compact systems of its kind available worldwide. Switchgear type 8DN8 combines technical expertise with all standards and advantages of the Siemens Energy 8D type series.

Main features:

  • For system voltages up to 170 kV
  • Rapid availability thanks to very short delivery and assembly times
  • Independent from atmospheric and external influences
  • Suitable for indoor and outdoor installation
  • Very space-saving configurations
  • Highly flexible switchgear arrangement for optimized system management
  • Adaptable to all predecessor models of the same voltage level
  • Very low levels of noise and field emission (EMC), making it possible to integrate switchgear into sensitive environments such as residential areas and city centers

8DN9 gas-insulated switchgear up to 245 kV

Our forward-looking 8DN9 switchgear are among the smallest in the world. We improved insulating materials and production methods, and optimized enclosure forms with modern casting technology to achieve this compact design.

Main features:

  • For onshore system voltages up to 245 kV
  • For offshore system voltages up to 300 kV
  • Compact, space-saving construction
  • Lightweight
  • Long service life
  • Very low levels of noise and field emission (EMC), making it possible to integrate switchgear into sensitive environments such as residential areas and city centers
  • Environmentally friendly

8DQ1 gas-insulated switchgear up to 550 kV

Type 8DQ1 is one of the world’s leading high-voltage switchgear. Siemens delivered the first gas-insulated substation for a rated voltage of 420 kV. A permanent process of improvement has led to today’s 8DQ1.

Main features:

  • For rated voltage of up to 550 kV
  • High degree of versatility provided by a modular design and active and passive modules

HIS 8DQ1 highly-integrated switchgear up to 550 kV

HIS – the gas-insulated switchgear for indoor and outdoor use needs less than half of the space of a comparable air-insulated substation. The 8DQ1-type HIS is a compact switchgear solution for a rated voltage of up to 550 kV. It is mainly used for cost-efficient renewals or expansions of air-insulated outdoor and indoor substations, particularly if the operator wants to make modifications while the switchgear is in service.


Main features:

  • For rated voltage of up to 550 kV
  • Compact because the circuit breakers, disconnectors, earthing switches and instrument transformers are housed in compressed gas-tight enclosures
  • Low-cost
  • Modular for indoor and outdoor uses
  • Environmentally friendly thanks to oil-free operating mechanism and extremely effective enclosure sealing

Global service

As a leader in the global market, we offer circuit breakers that meet the differing environmental, technical and economic conditions of countries around the world. In 150 countries around the world there are 136,000 of our circuit-breakers in use.