Overview
Fully Insulated Switchgear (FIS) represents a significant advancement in medium-voltage power distribution technology. These compact, modular units encapsulate all live components in solid insulation material, typically epoxy resin, eliminating the risk of phase-to-phase or phase-to-ground faults. The technology originated in Europe during the 1960s as a safer alternative to air-insulated switchgear, gaining global adoption due to its reliability in harsh environments. Modern FIS units integrate circuit breakers, disconnectors, earthing switches, and protection devices in a single, maintenance-free enclosure. They are particularly valued in urban power networks where space constraints and safety regulations demand robust, compact solutions. Leading manufacturers continue to innovate with smaller footprints and digital monitoring capabilities.
Structure and Working Principle
The core design features three-phase busbars completely encapsulated in epoxy resin insulation, with silicone rubber interfaces ensuring airtight sealing. Vacuum interrupters handle current breaking duties, while gas-insulated or solid-insulated designs manage dielectric requirements. The modular construction allows for various configurations including ring main units and transformer feeders. Operation follows standard switchgear principles with enhanced safety: rotating insulated actuators control switch positions without exposing operators to live parts. Advanced models incorporate SF6-free designs using vacuum switching technology and solid insulation, addressing environmental concerns while maintaining performance. The complete encapsulation provides IP65 or higher protection against dust and moisture ingress.
Key Features
FIS delivers exceptional dielectric performance with insulation levels exceeding 36kV for 12kV rated equipment. The solid insulation system remains stable across temperature ranges from -40°C to +70°C, unaffected by humidity or pollution. Compact dimensions (typically 30-50% smaller than conventional switchgear) enable installation in confined spaces like high-rise buildings or underground networks. Maintenance requirements are significantly reduced compared to air-insulated alternatives - no periodic cleaning of insulators or lubrication of mechanical parts. Modern versions feature condition monitoring sensors for partial discharge detection, temperature monitoring, and mechanical operation counters. The designs meet IEC 62271-200 standards with optional compliance with local grid codes for utility applications.
Application Areas
Primary applications include secondary substations in urban areas where space optimization and public safety are critical. Industrial plants favor FIS for chemical resistance in aggressive environments like petrochemical facilities or paper mills. Mining operations benefit from the vibration resistance and compact layouts suitable for mobile substations. The technology has expanded into renewable energy applications, particularly in wind farm collector stations and solar PV plants where salt spray corrosion poses challenges. Data centers increasingly specify FIS for its reliability in critical power distribution. Specialized versions serve railway electrification and offshore platforms where maintenance access is limited.
Maintenance and Precautions
While designed for minimal maintenance, periodic inspections should verify insulation resistance (minimum 1000MΩ) using megohmmeters. Infrared thermography during operation helps detect abnormal heating at cable connections. Manufacturers recommend functional testing of mechanical interlocks and switch mechanisms every 3-5 years. Critical precautions include ensuring proper earthing before any internal inspection - even with insulation, induced voltages may exist. Only trained personnel should perform maintenance using manufacturer-approved procedures. Environmental considerations include proper disposal of epoxy components at end-of-life, though modern formulations use recyclable materials. Storage of spare units requires climate-controlled conditions to prevent moisture absorption in insulation.
B2B Procurement Guide
When sourcing FIS, prioritize manufacturers with type-test certifications from recognized labs like KEMA or CESI. Key specifications to confirm include rated short-circuit current (typically 20-25kA), internal arc classification (IAC AFLR classes), and seismic withstand capability. Delivery lead times average 12-16 weeks for standard configurations. Total cost analysis should factor in reduced civil works (smaller foundations) and lower lifetime maintenance compared to conventional switchgear. For large projects, consider panel-builders offering pre-assembled substation solutions. Emerging markets show increasing localization with regional production hubs in Asia and Eastern Europe offering competitive pricing while maintaining European technology standards.
Related Manufacturers
- 主营：[]
- 主营：[]
- 主营：配电柜、箱式变电站、配电箱、开关柜、储能柜、母线槽、箱变、变压器、环网箱、电缆分支箱、预制舱、充电桩
- 主营：真空断路器、一二次融合真空断路器、户外真空断路器、低压开关柜、高压开关柜、高压真空断路器、户外高压断路器、电容补偿柜、中置柜、负荷开关、隔离开关、充气柜、电缆分支箱、氧化锌避雷器、智能真空断路器、KYN28、高压中置柜、环网柜、箱变、箱式变电站、高压电缆分支箱、低压抽屉柜、低压无功补偿柜、35KV电缆分支箱
- 主营：c负荷开关柜、全密封充气柜、高低压开关柜、矿用高低压开关柜、开关电缆分接箱、环网箱、开闭所
- 主营：高压开关柜、低压开关柜
- 主营：箱式变电站、高压环网柜、高压开闭所、全绝缘充气柜、GGD低压开关柜、光伏柜、光伏预制舱、成套配电箱、KYN28高压中置柜、动力柜、MNS抽屉柜、低压配电柜、景观式地埋箱变、PT柜、计量柜、进线柜、充气柜、环网柜、配电箱、XL-21动力柜、GCK低压抽屉柜、不锈钢电容柜
- 主营：配电柜、变频柜、配电箱、开关柜、plc控制柜、控制柜、动力柜、变频器、伺服器
- 主营：冷缩电缆附件、真空断路器、氧化锌避雷器、绝缘子、复合式支柱绝缘子、全绝缘充气柜、热缩电缆附件、六氟化硫断路器、负荷开关、隔离开关、电缆分支箱、箱式变电站、热熔式中间接头、充气柜、环网柜、低压配电柜、光伏预制舱、不锈钢配电箱、干式电力变压器、高压电流互感器、冷缩电缆终端头、光伏高低压并网柜
- 主营：中置柜、真空断路器柜、箱式变电站、高低压开关柜、高压开闭所、固体柜、充气柜、环网柜、高压分支箱、一次二融合环网柜、光伏预制舱
- 主营：充气柜、环网柜、箱变、高压开关柜、全绝缘充气柜、低压开关柜、开闭所、电缆分支箱、低压抽屉柜、低压配电柜、箱式变电站、高压中置柜、真空断路器、负荷开关、隔离开关、高压充气柜、高压环网柜、欧式箱变、高压电缆分支箱、KYN28、固体柜、环保柜、中置柜、六氟化硫断路器、跌落式熔断器
- 主营：环网柜、看门狗、电表箱、开关柜、固体绝缘、高压绝缘、hxgn15-12、固定柜、真空带、熔断器、户外箱、中置柜、断路器、控制箱、10kv电缆、zw32真空、cyrm-12630a、zw32zw32-12、高压交流、开关智能、开关设备、终端装置、电缆分接、户外高压、隔离开关
- 主营：光伏预制舱、高低压成套设备、动力配电柜、高压开关柜、中置式开关柜、高低压开关柜、低压开关柜、箱式变电站、箱式变压器、电力光伏预制舱、光伏升压预制舱、美式箱变、欧式箱变、景观式箱变、充电桩箱式变电站、充电桩箱变、光伏升压箱变、干式变压器、油浸式变压器、三相干式变压器、分布式光伏预制舱、35kV光伏预制舱、光伏电站预制舱
- 主营：配电柜、欧式箱变、美式箱变、高压开关柜、全绝缘高压环网柜、成套抽屉式开关柜、GCK低压开关柜、低压抽屉式开关柜、电缆分接箱、高压中置柜、高压环网柜、高压充气柜、低压抽屉柜、箱式变电站、充气柜、环网柜、户外预装式箱式变电站、10kV电缆分支箱、GGD交流低压配电柜、不锈钢JP柜、进出线柜
- 主营：高压电缆分支箱、充气柜、环网柜、开闭所、户外高压智能真空断路器、一二次融合断路器、跌落式熔断器、高压避雷器、真空断路器、电缆分支箱、交流接触器线圈、避雷器计数器、避雷器、真空断路器储能电机、进线柜
- 主营：高压成套、欧式电缆分支箱、电缆保护接地箱、高压开关柜、电缆交叉接地箱、电缆冷缩附件、低压配电柜、高压环网柜
- 主营：补偿柜、壁挂箱、软启动、开关柜、配电箱、变频器、温控柜、控制柜、软动器、配电柜、变频柜、低压控制柜、电气控制、水泵变频柜
- 主营：配电箱、配电柜、变压器、开关柜、高压开关柜、低压开关柜、箱式变电站、箱式变压器、箱变、干式变压器、电力变压器、高压配电柜、低压配电柜、电柜、电箱、预制舱变电站、动力柜、控制柜、防爆配电箱、变频柜、计量表箱、电缆分支箱、成套配电柜、动力配电柜