Medium and High Voltage Switchgear

Insulation materials used in Medium and High Voltage Switchgear (12kV–40.5kV) can be broadly classified into laminated insulation materials, insulation support components, flexible insulation materials, cast resin insulation components, molded insulation components, and specialty insulation materials. These materials play critical roles in electrical insulation, mechanical support, arc resistance, tracking resistance, and high-temperature protection, ensuring the safe and reliable operation of switchgear systems.

1. Laminated Insulation Materials

2. Insulation Support Components

3. Flexible Insulation Materials

4. Classification by Switchgear Compartment

5.Mainstream Material Configuration（12kV–40.5kV Switchgear）

Industry Trends

In the 12kV–40.5kV medium-voltage switchgear industry, GPO-3, FR-4, APG cast epoxy resin components, and SMC molded insulation parts have become the mainstream insulation solution.

Among these materials:

GPO-3 is widely used for busbar supports and insulation barriers due to its excellent arc resistance, flame-retardant performance, and tracking resistance.
FR-4 is commonly utilized for precision-machined structural insulation components because of its superior electrical and mechanical properties.
SMC molded insulation components are extensively used in insulation covers and enclosures because of their excellent flame resistance, mechanical strength, and moisture resistance.
APG cast epoxy resin components are the core materials for contact boxes, bushings, and post insulators, offering high dielectric strength and dimensional stability.
As the demand for renewable energy substations, smart grid infrastructure, and advanced power distribution systems continues to grow, the adoption of G11 high-temperature laminates and NMN Class H insulation materials is steadily increasing, driven by the need for enhanced thermal performance and long-term operational reliability.