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Standard: IEC60893-3:2003, GB/T 1303.4-2009
Regular Size: 1020*1220 /1020*1020 /1220*2040 /1220*2440 mm(support customize)
Standard Thickness: 0.5-80mm
Thermal rating: Class H (180℃)
Flame resistance:UL94-HB
Color: yellow/brown/Green/Light Green
Application:Motors,Generators,Transformers,Switchgear,Circuit Breakers
EPGC 308 Epoxy Fiberglass Sheet (corresponding to G11-H under NEMA standards or EPGC 308 under IEC standards) is a high-performance Class H epoxy glass cloth laminated sheet. It is manufactured by impregnating electrical-grade alkali-free fiberglass cloth with high-(glass transition temperature) epoxy resin, followed by hot pressing under high temperature and pressure.
Compared to standard FR4 or G10 the core advantage of EPGC 308 lies in its exceptional heat resistance and its ability to maintain mechanical strength at high temperatures.
Superior Heat Resistance: Classified as a Class H insulating material, with a long-term operating temperature of up to 180°C.
High-Temperature Mechanical Strength: It retains over 50% of its room-temperature flexural strength (typically ≥250MPa) even at temperatures of 150°C or higher.
Electrical Stability: Offers excellent dielectric properties and resistance to tracking (CTI) even in high-humidity environments.
Corrosion and Radiation Resistance: Highly resistant to various chemical solvents and remains stable under radiation exposure.
Machinability: Supports CNC milling, drilling, sawing, and cold punching.
EPGC 308 (G11-H) is primarily utilized for slot wedges and end supports in traction motors and large-to-medium generators, as well as insulating spacers and frames in dry-type transformers. It is also a critical structural material for busbar clamps and components in high-voltage switchgear that must withstand significant electrodynamic forces, making it the core solution for high-heat, heavy-load, and precision insulation requirements in power systems.
1.Factory: We operate a professional electrical insulation materials manufacturing facility and are ISO-certified.
2.Fully Automated Production: Our advanced automated workshop is supported by a strict and comprehensive quality management system.
3.Quality Inspection: Equipped with four major laboratories and five core product performance testing capabilities.
4.Processing Services: We provide customized processing solutions based on your requirements, ensuring high quality and on-time delivery.
5.Product Certification: Our products comply with UL, SGS, RoHS, and REACH standards. Sample testing is available upon request.
6.Ready Stock Supply: Standard products can be delivered within 7–15 days.
Our company is certified to ISO 9001, ISO 14001, and ISO 45001 management systems. Our products also comply with international certifications and reports including UL, RoHS, REACH, MSDS, CEMT, as well as factory inspection and test reports provided before shipment.
| General Properties： | ||
| Property | Unit of measure | Typical Value |
| Density | gc/m3 | 1.90-2.05 |
| Water Absorption (5mm) | % | ≤0.04 |
| Flame Retardant | UL94 | – |
| Electrical Properties： | ||
| Property | Unit of measure | Typical Value |
| Electrical Strength ⊥ | kV/mm， thickness=3mm | ≥10.2 |
| Electrical Strength ∥ | kV | ≥45 |
| Tracking Resistance | PTI | – |
| Insulation resistanceafter immersion | MΩ | 5*104 |
| Mechanical Properties： | ||
| Property | Unit of measure | Typical Value |
| Flexural Strength | MPa | ≥340 |
| Tensile Strength | MPa | ≥300 |
| Compressive Strength ⊥ | MPa | ≥350 |
| Modulus Of Elastricity | MPa | ≥24000 |
| Impact Strength ∥ | kJ/m2 | ≥50 |
| Thermal Properties： | ||
| Property | Unit of measure | Typical Value |
| Thermal Charactersitices | ℃ | 180 |
| Notes： | ||
| Disclaimer: The above values are based upon routine test data and do not form the basis of a supply contract. These products may be used in a diverse range of applications and whilst every effort is made to ensure the information in this data sheet is accurate, it must be stressed that it is the user’s responsibility to ensure suitability for the intended end use. | ||
