Surge Arrestors, Class C
Engineered for Spark-Free Protection in Demanding Conditions
Insulect’s Class C Surge Arresters are designed to protect low-voltage electrical installations from overvoltage transients resulting from indirect lightning strikes and switching operations. These arresters are suitable for installation downstream of the main distribution board, providing an additional layer of protection for sensitive equipment.

- 01 Application Overview
- 02 Spark-Free Surge Arresters
- 03 Polymeric Surge Arresters
- 04 What We Solve For
Spark Free Technology
Offering spark-free technology in a compact form, Class C arresters are ideal for installation in confined or indoor environments. With no external sparking or venting, they’re safe to install near sensitive electronics, buildings, and personnel, delivering discrete, continuous protection with zero maintenance.
Engineered for Safety
Insulect’s Class C arresters are built with polymeric insulation that resists moisture, UV degradation, and mechanical stress. The result is a robust, non-corrosive enclosure that supports a long service life and consistent protective performance in fluctuating low-voltage environments.
Reliable Medium Voltage Protection, Built to Standards.
Engineered for distribution network applications, Class C arresters deliver consistent protection from transient overvoltages—supporting system stability and asset longevity in typical service conditions.
Reducing Risk. Enhancing Longevity.
Available from 3 kV to 36 kV, Class C arresters meet IEC 60099-4 and IEEE C62.11 standards, with 5 kA discharge current ratings, ensuring compliance for distribution-level protection across diverse utility needs.
Features & Functionality

Class C surge arresters are independently tested to AS 1307.2-1996 (R2015), ensuring zero spark production—ideal for bushfire-prone or sensitive environments.

Designed for horizontal or vertical applications, and may be mounted on steel structures or pole mounted.

Built to perform under high-stress conditions, our arresters are proven to withstand the overvoltage demands of REFCL (Rapid Earth Fault Current Limiter) networks.

Available from 3 kV to 64 kV, with 5 kA and 10 kA discharge current ratings, our Class A range complies with IEC 60099-4 and IEEE C62.11, ensuring global compatibility and performance across distribution and sub-transmission networks.
Functionality & Options
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Designed for general distribution protection where visible spark operation is not a requirement.
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Lightweight polymer housing and fibreglass-reinforced core enable simple and secure mounting across poles or steel structures.
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Suitable for urban, rural, or industrial networks, delivering consistent protection from transient overvoltage events.
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Fully sealed with HTV silicone to ensure durability against moisture, dust, and UV exposure.
Key Technical Specifications
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Voltage Rating Range: 3 kV – 36 kV
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Discharge Current Ratings: 5 kA
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Arrester Class: Class C (Polymer Distribution)
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Standards Compliance: IEC 60099-4:2004, ANSI/IEEE C62.11:2005
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Housing Material: High-temperature vulcanised (HTV) silicone with fibreglass-reinforced internal structure
Our Projects Featuring Insulect Switchgear
Explore our project highlights to see where Insulect Switchgear is making an impact.
For tailored advice on whether this solution suits your network, please connect with our team here.
Where you'll find our Switchgear
You'll find Insulect-supplied and installed Switchgear across Australia and New Zealand.





Why Choose Insulect for Surge Arresters
Insulects surge arresters deliver proven performance in protecting medium voltage assets against lightning and switching overvoltage events. Whether you're operating in bushfire-prone zones or compact substations, our Class A spark-free and Class C polymeric designs are engineered for safety, durability, and ease of installation. Backed by compliance with IEC and AS standards, and trusted in networks across Australia and New Zealand, our arresters help safeguard transformers, switchgear, and cable systems with confidence.
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.
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.
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.
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.
We are able to oversee every phase from concept to completion, providing comprehensive solutions that simplify complex projects and ensure successful outcomes.