92051247 - Tweco GC-500 Heavy Duty Steel Ground Clamp with Copper Shunt

Technical Overview of the Tweco GC-500 Ground Clamp

The Tweco GC-500 (Part Number: 9205-1247) is a high-performance work clamp designed for heavy-duty industrial welding applications requiring up to 500 amperes. This unit is engineered to solve common failure points found in standard ground clamps through its hybrid material construction. The body is fabricated from zinc-plated steel, providing exceptional mechanical strength and resistance to deformation under the high tension of the spring. This ensures that the clamp maintains a tight bite on the workpiece over years of service, unlike softer copper-alloy bodies which may deform.

Crucially, the GC-500 features a woven copper shunt that bridges the two jaw handles. In traditional clamps, welding current often passes through the hinge pin, leading to arcing, heating, and eventually fusing the hinge, rendering the clamp useless. The copper shunt in the GC-500 provides a low-resistance path for the current, bypassing the hinge mechanism entirely. This design not only extends the lifespan of the tool but also ensures consistent voltage delivery to the arc by minimizing voltage drop at the ground connection.

The clamp features a generous 2-inch jaw opening, allowing it to attach to a wide variety of plate thicknesses, pipes, and structural members. The cable connection utilizes a ball-point screw mechanism, which aggressively secures the welding cable (accommodating sizes up to 4/0) against the clamp body, ensuring a vibration-resistant electrical interface. The zinc plating offers moderate corrosion resistance in shop environments.

Key Specifications

• Amperage Rating: 500 Amps @ 60% Duty Cycle
• Body Material: Zinc Plated Steel
• Conductivity Element: Woven Copper Shunt
• Jaw Opening: 2 Inches (50.8mm)
• Cable Connection: Ball Point Screw
• Cable Capacity: 3/0 to 4/0 AWG