The Silicone Thermal Pad TO-30 (42mm x 29mm) is an oversized, thermally conductive, and electrically insulating interface pad specifically designed for mounting large power semiconductor modules, heavy-duty industrial transistors, bridge rectifiers, and solid-state devices directly to metal heatsinks. Constructed from high-grade silicone elastomer reinforced with an anti-tear fiberglass substrate, these large-format pads deliver robust dielectric isolation exceeding 4.0kV AC to prevent high-voltage arcing while bridging microscopic surface irregularities to maximize thermal dissipation. Supplied in a bulk 1000-piece pack, they are ideal for high-power electronics manufacturing, renewable energy systems, industrial inverter assembly, and repair facilities.

Specifications

• Product Type: Thermally Conductive Electrical Insulator Pad
• Compatible Packages: TO-30 
• Dimensions: 42mm (Length) x 29mm (Width) (Industrial Large-Format)
• Thickness: 0.3mm (±0.05mm)
• Mounting Holes: Pre-punched mounting screw holes tailored for standard large module layouts
• Material: High-Grade Silicone Elastomer with Woven Fiberglass Core Reinforcement
• Thermal Conductivity: 1.2 W/m·K to 1.5 W/m·K
• Dielectric Breakdown Voltage: ≥ 4.0 kV AC (4000V)
• Volume Resistivity: ≥ 1.0 × 10¹² Ω·cm
• Operating Temperature Range: -50°C to +200°C
• Flammability Rating: UL94 V-0 equivalent flame retardant
• Pack Quantity: 1000 Pieces (Full Bulk Pack)

Features

• Large-Format 42x29mm Surface Area: Provides generous surface coverage and extended creepage distance for oversized power devices, preventing flashover or edge arcing at high operational voltages.
• High Dielectric Isolation (4kV+): Reliably isolates high-voltage live module bases and transistor tabs from grounded aluminum heatsinks and chassis enclosures.
• Fiberglass Reinforced Core: Eliminates tearing, puncture, and stretching under heavy clamping pressures or over rough machined heatsink surfaces.
• Pre-Cut & Pre-Punched Design: Precision stamped for fast, drop-in assembly on high-volume production and industrial wiring lines without manual trimming.
• High Thermal Stability (-50°C to +200°C): Retains elasticity, compression compliance, and thermal conductivity without drying out, cracking, or hardening over decades of use.
• Clean & Reusable Assembly: Clean dry-mount alternative to messy thermal grease alone, preventing oil migration and reducing cleanup labor.

Common Applications

• High-Power Semiconductor Modules: Thermal isolation for oversized multi-transistor power blocks, dual IGBT modules, and heavy SCR assemblies.
• High-Current Bridge Rectifiers: Heatsink isolation for single-phase and three-phase industrial bridge rectifiers (e.g., KBPC/QL series).
• Industrial Solar Inverters & Wind Converters: High-capacity power switching stages and energy reclamation units mounted on common busbar heatsinks.
• Industrial Motor Drives & Soft Starters: Thermal management for three-phase motor drives, CNC spindle drives, and traction inverters.
• High-Wattage Power Supplies & Welding Inverters: Primary power stage isolation in heavy-duty commercial switch-mode power supplies.

Usage Tips

• Surface Cleaning: Clean both the heatsink surface and the device baseplate thoroughly to remove any metal shavings, dust, burrs, or oil residue prior to installation.
• Insulating Bushings: Always install matching nylon or plastic shoulder washers/bushings on mounting screws to ensure the screw heads do not bridge electrical potential to the grounded heatsink.
• Uniform Clamping Torque: Tighten mounting screws in a balanced cross-pattern (recommended 0.8 to 1.2 N·m depending on device specifications) to ensure flat, even contact pressure without warping the module baseplate.
• Micro-Thin Thermal Paste (Optional): In continuous ultra-high-power applications, applying a thin, uniform haze of thermal grease to both faces of the pad will further eliminate micro-air gaps and optimize heat transfer.