How to Choose the Right Insulation Board Thickness and Grade

Selecting the right insulation board comes down to four questions: What voltage? What temperature? What mechanical load? And do you need flame retardancy?

1. Temperature class

Match the board's temperature class to your operating temperature: Class B (130 °C), Class F (155 °C) or Class H (180 °C). For high-temperature motors and transformers, choose 3250, 3255 or Class H halogen-free grades.

2. Mechanical strength

For structural parts, choose high-strength grades like G-10, G-11 or 347. For machined gears and bushings, phenolic grades like 3025B are ideal.

3. Flame retardancy

If fire safety standards apply, choose FR-4, FR-5 or a halogen-free grade rather than non-flame-retardant G-10 or G-11.

4. Thickness

Thickness is driven by dielectric and mechanical requirements. We supply most grades from 0.5 mm to 100 mm and can CNC cut to your exact dimensions. Contact our technical team for a recommendation.