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Substation Disconnectors
and Earthing Switches

Up to 145 kV
Rotary Double-Break

Air-insulated disconnectors, isolators, and earthing switches for high-voltage substations up to 145 kV.

Insulect’s air-insulated disconnectors, isolators, and earthing switches are designed for outdoor high-voltage substations (12–145 kV). Their robust rotary double-break design ensures visible isolation and reliable switching under harsh conditions. Suitable for cable sectionalising, transformer and motor switching, and ring networks, they can be tailored for new or retrofit substations. Configurations include manual or motorised operation, optional earthing switches, and integration with substation control systems.

Made for Demanding Environments

Insulect disconnectors are trusted and field-proven across utility, renewable, and industrial high-voltage applications. Featuring a durable rotary double-break design, they provide reliable visible isolation and enhanced operational safety in all conditions. Available in manual or motorised configurations, and adaptable for horizontal or vertical mounting, these units are engineered to integrate seamlessly into both new installations and existing substation infrastructure.

Engineered for Precision. Built for the Field.

Insulect’s substation disconnectors are engineered for high-performance isolation in medium- to high-voltage networks, with models available from 12 kV to 145 kV. Built on a proven rotary double-break design, each unit provides visible isolation, mechanical durability, and safe operation in outdoor environments, including high-contamination and remote sites. Disconnectors can be supplied in either horizontal or vertical configurations, with manual or motorised operation, and optional integrated earthing switches. All designs are compliant with IEC and AS standards and are manufactured and tested in Australia to meet local network conditions and requirements.

Every disconnector is tailored to suit the specific layout and operational needs of your substation. Options include auxiliary switches for control system integration, mechanical and electrical interlocks for enhanced safety, and flexible mounting to suit new builds or retrofit installations. Insulect also offers complete lifecycle support—including installation, training, site refurbishment, and custom replacement solutions—to ensure long-term performance and minimal downtime. Whether you're specifying equipment for a greenfield site or upgrading aging infrastructure, our disconnectors are built to deliver long-term reliability with low maintenance overhead.

Engineered Earthing Switches for Substation Safety

Insulect’s earthing switches are designed to provide safe and reliable grounding of high-voltage equipment during maintenance, testing, or emergency procedures. Built for substation environments and available as single or double units, these switches can be mounted independently or integrated directly with disconnectors for space and operational efficiency.

Engineered for compatibility with Insulect’s full disconnector range, earthing switches are available in both manual and motorised configurations and can be fitted with mechanical interlocks and auxiliary switches for enhanced control and safety. Each unit is customisable to suit your network’s voltage level, structure type, and operational protocols. Whether used in new substations or as part of retrofit upgrades, Insulect earthing switches deliver the mechanical durability, switching integrity, and compliance required in today’s HV networks.

What We Solve For

Disconnectors must perform under pressure: high fault currents, corrosive environments, and extended inactive periods. Insulect’s range solves common operational challenges with features like spring-loaded flickers for arc suppression, IP65 motor drive enclosures for remote control, and custom footprints to suit brownfield installations. Our products minimise total cost of ownership through long-life operation, low maintenance requirements, and locally available support.
TECHNICAL

Features & Functionality

Functionality & Options

  • Disconnectors isolate sections of a power network to allow safe maintenance and operation of electrical equipment.

  • Integrated or independent earthing switches can ground circuits to ensure safety during maintenance or fault conditions. 

  • The switches can be manually operated or motor-driven, allowing both local operation and remote control from a control room.

  • Auxiliary switches enable substation control systems to monitor the status (open/closed) of disconnectors and earthing switches.

  • Mechanical or electrical interlocks prevent unsafe operations, such as operating the earthing switch when the disconnector is closed.

Key Technical Specifications

  • Voltage range: 12 kV to 145 kV

  • Current ratings: 600 A to 3500 A continuous

  • Short-circuit withstand: Up to 50 kA for 3 seconds

  • Mechanical endurance: M1 class, 2,000 operations (AS 62271.102-2005 & AS 2650-2005)

  • Lightning impulse withstand voltage (LIWV): Up to 650 kVp

EXPERIENCE

Our Projects featuring Insulect Disconectors

Explore our project highlights to see where Insulect Disconnectors are making an impact.
For tailored advice on whether this solution suits your network, please connect with our team here.

Where you'll find our Substations

You'll find Insulect-supplied and installed Substations across Australia and New Zealand -- our locally built Insulect range and imported Sieyuan range.

ADVANTAGES

Why Choose Insulect for Substation Disconnectors

Insulect's disconnectors are field-proven across utility, renewable, and industrial high-voltage networks. Built on a robust rotary double-break design, they deliver reliable visible isolation and operational safety in the harshest environments. Whether manual or motorised, horizontally or vertically mounted, our disconnectors are designed for seamless integration into both new builds and existing substation infrastructure.
 
Engineered for Local Conditions
Designed, manufactured, and tested in Australia, our disconnectors are built to perform in high-contamination, high-temperature, and remote-area environments. Every unit is tailored to suit local network specifications and compliance requirements.
Flexible Configurations
From 12 kV to 145 kV, Insulect offers manual or motorised units, with options for earthing switches, auxiliary switches, and interlocks. Custom footprints and mounting options ensure a perfect fit for greenfield and brownfield installations alike.
End-to-End Support
We offer more than just hardware—our team provides complete lifecycle support, from engineering advice and on-site installation to training, refurbishment, and retrofit solutions. With local service and fast turnaround, we’re a partner you can rely on.
IMPLEMENTATION

Services & Support

Insulect offers comprehensive services and support for the products we manufacture and specialise in, enhancing value for local utilities, major energy users, equipment manufacturers, and service operators. 

LOCAL TECHNICAL TEAM

Our local technical team provides exceptional support and expertise, ensuring quick response times and personalised service to tackle any challenges that may arise during project execution.

 
ENGINEERING DESIGN

Our team utilises advanced technology and industry knowledge to develop innovative and efficient high-voltage switchgear solutions, customised to fit the unique requirements of each project.


 
PROCUREMENT & LOGISTICS

We facilitate smooth procurement and logistics processes by sourcing from trusted, proven partners and coordinating timely deliveries, ensuring projects remain on schedule and within budget.


 
TESTING & COMMISSIONING
Professional testing and commissioning support ensure that every high-voltage switchgear system functions safely and reliably, adhering to all regulatory standards and client expectations.
 
TURNKEY PROJECT DELIVERY

We are able to oversee every phase from concept to completion, providing comprehensive solutions that simplify complex projects and ensure successful outcomes.

 
FACTORY VISITS
We facilitate client visits to our local manufacturing sites here in Australia, as well as overseas, for initial inspection as well as factory acceptance testing.
 
FROM THE BLOG

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Ready to Strengthen Your Network?

We built for reliability, safety, and compliance — our products are designed to perform in the toughest environments. Talk to our team to ensure you're specifying the right product for your application.