A PV solar mid clamp is a mechanical fastening device used to secure two adjacent solar modules side-by-side to the same mounting rail. Its defining characteristic is its symmetric design, featuring two opposing pressure plates or lips that simultaneously clamp the frames of neighboring panels, holding them securely to the rail below .

Core Functional Principles

• Dual Module Retention: The primary function is to clamp the frames of two adjacent solar panels to the mounting rail, preventing movement due to wind uplift, gravity loads, and thermal expansion .

• Inter-Module Spacing: Mid clamps maintain a consistent, manufacturer-specified gap between adjacent modules. This gap accommodates thermal expansion of the frames and prevents glass-on-glass contact that could lead to micro-cracking .

• Grounding Path Establishment: Most mid clamps incorporate integrated grounding features (such as penetrating teeth) that establish an electrical bond between both module frames and the mounting rail, ensuring a continuous equipment grounding path .

Material Composition

• High-Strength Aluminum Alloy: The main body is typically die-cast or machined from corrosion-resistant aluminum alloys, commonly AL6005-T5 or 6061-T6 . This provides:

• Structural Strength: Withstands clamping forces and environmental loads .

• Light Weight: Ease of handling during installation .

• Corrosion Resistance: Natural oxide layer protects against weathering .

• Stainless Steel Hardware: The clamping bolt (and any integrated threaded components) is made from stainless steel (SUS304 or A2) to prevent galvanic corrosion and ensure long-term clamping force .