GPO-3 Insulation Sheets
GPO-3 is a high-performance, fiberglass mat-reinforced thermoset polyester laminate designed for demanding electrical insulation applications. Manufactured by impregnating continuous strand fiberglass mats with polyester resin and curing under controlled heat and pressure, GPO-3 sheets deliver an exceptional combination of dielectric strength, arc resistance, flame retardancy, and mechanical durability. Compliant with NEMA GPO-3 standards and rated UL 94 V-0, these sheets are the preferred insulation material for switchgear, distribution panels, transformers, and a wide range of power equipment.
Key Advantages
Lead Time
15-25 Days
MOQ
100 pieces
Sample
Available
Technical Specifications
| Parameter | Value |
|---|---|
| Standard | NEMA GPO-3 / UL 94 V-0 |
| Material | Glass Mat Reinforced Polyester |
| Dielectric Strength | 300–500 V/mil |
| Flexural Strength | ~20,000 psi (ASTM D790) |
| Compressive Strength | ~30,000 psi (ASTM D695) |
| Max Operating Temp | 130°C (265°F) continuous |
| Thickness Range | 1.0 – 50.0 mm |
| Sheet Size | 1000×2000 mm / 1220×2440 mm (custom available) |
Material Information
Available Sizes & Customization
We offer a wide range of standard sizes and specifications. Custom dimensions, materials, and finishes are available upon request.
Application Scenarios
Low-voltage switchgear insulation barriers
Busbar insulation supports and spacers
Power distribution panel backers
Transformer coil supports and core blocking
Motor control center insulation panels
Arc chutes and arc flash isolation panels
New energy and rail transit electrical systems
Industrial electrical equipment insulation
Manufacturing Process
Material Selection
NEMA-grade GPO-3 laminate sheets sourced from certified manufacturers
CNC Programming
CAD/CAM programming for precision cutting, drilling, and milling operations
CNC Machining
Multi-axis CNC machining centers for complex insulation part geometries
Surface Finishing
Deburring, edge chamfering, and surface treatment for optimal electrical performance
Electrical Testing
Dielectric strength, insulation resistance, and arc resistance verification
Cleanroom Packaging
Dust-free packaging to maintain surface cleanliness for electrical applications
Custom Insulation Solutions
We specialize in custom-machined electrical insulation components from GPO-3, FR4, G10, and other laminate materials. Our CNC machining capabilities allow us to produce complex insulation parts to your exact specifications.
Our Capabilities
Quick Reference
| Minimum Order Quantity | 100 pieces |
| Lead Time | Standard sheets: 3-5 days | Custom machined: 10-15 days |
| Sample Availability | Samples available within 5-7 days; material samples free of charge |
| Payment Terms | T/T, L/C, Western Union |
| Trade Terms | FOB, CIF, DDP, EXW |
Packaging & Delivery
Insulation products require careful handling to prevent surface contamination and mechanical damage.
Packaging Options
- Individual wrapping with PE film protection
- Foam-lined cartons for machined parts
- Wooden crate for sheet materials
- Vacuum-sealed packaging for sensitive components
Shipping Methods
- FOB
- CIF
- DDP
- EXW
Loading Ports: Shanghai Port, Ningbo Port
Export Experience
- Exported to 50+ countries
- 15+ years of export experience
- Professional export documentation
- Experienced freight forwarder network
Quality Control
Our insulation products undergo comprehensive electrical and mechanical testing to ensure they meet NEMA and IEC standards.
Inspection Process
Material Verification
Incoming laminate sheets verified against NEMA/IEC specifications
Dimensional Inspection
CNC-machined parts measured with CMM for critical dimensions
Electrical Testing
Dielectric strength, insulation resistance, and arc resistance testing
Visual Inspection
Surface quality, edge finish, and contamination check under magnification
Documentation
Complete test reports, material certificates, and certificates of conformance
Certifications & Standards
Factory Capabilities
Factory Area
5,000 m²
Export Markets
50+ Countries
Experience
15+ Years
Annual Capacity
2,000,000 pcs
Frequently Asked Questions
Request a Quote
Interested in GPO-3 Insulation Sheets? Fill out the form below and our sales team will respond within 24 hours with pricing, specifications, and lead time information.
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