Fastronix Solutions 300A Battery Disconnect Switch 1/2" Copper Studs with Face Plate - Severe Duty, 2000A Surge

The Fastronix 300A 1/2" Severe Duty Battery Disconnect Switch with Face Plate is a heavy-duty, serviceable power-isolation switch engineered to safely cut battery power in 12V systems up to 300 amps continuous and withstand 2000 amps intermittently.

This compact, rugged disconnect switch combines high-current capability with installation flexibility. Built with 1/2" copper main studs and an index pin to prevent post-installation rotation, it’s designed for vehicles, industrial equipment, marine vessels, and backup power systems where reliable battery isolation and corrosion-resistant connections matter. The face plate provides a clean, finished appearance for panel mounting, and optional auxiliary studs let you wire an indicator or small accessory without compromising the main circuit.

How does this switch handle high current and short bursts of demand?

The Fastronix switch uses beefy 1/2" copper main studs rated for 300A continuous at 12VDC with the ability to tolerate 2000A intermittent surges, so it copes with both steady loads and brief inrush currents. Its construction helps reduce voltage drop and hot spots under heavy use.

• 1/2" copper main studs for low-resistance connections
• 300A continuous rating at 12VDC for sustained loads
• 2000A intermittent rating for surge and cranking currents
• Robust materials for improved thermal performance and longevity

Can I use it for single-pole and dual-pole setups, and what changes are required?

Yes—this model supports both single-pole and dual-pole configurations. The internal contacts and stud layout allow flexible wiring; for dual-pole use, follow wiring diagrams and fitment clearances recommended for your application to maintain safe isolation.

• Single-pole: isolate one battery or power feed quickly
• Dual-pole: isolate two circuits when dual isolation is required
• Follow torque specs for copper studs to ensure secure connections
• Reference installation guide for orientation and face-plate cutout

What accessory or indicator options are available with the auxiliary studs?

The switch includes smaller auxiliary studs rated to 20A@12VDC for powering indicator lights, relays, or small accessories. These provide a safe way to signal switch position or feed low-current control circuits without routing additional wires to the primary terminals.

• Auxiliary studs: 20A@12VDC for lights or control circuits
• Use for an LED indicator showing ON/OFF status
• Keep accessory wiring separate from main battery conductors
• Ideal for control of relays that switch larger loads downstream

How does the design simplify installation and prevent post-installation issues?

The unit includes an index pin that locks the switch body orientation after mounting, preventing rotation from vibration or cable strain. A matching face plate offers a finished panel look and helps protect the mounting surface, while compatibility with Fastronix 404-116 terminal covers lets you tidy connections and meet safety preferences.

• Index pin secures orientation to prevent rotation under load
• Face plate provides clean panel appearance and secure mounting
• Compatible with Fastronix 404-116 terminal covers for protection
• Standard stud sizes ease integration with common battery cable lug sets

Who is this for? The Fastronix 300A Severe Duty Battery Disconnect Switch is suited to mechanics, fleet operators, marine electricians, RV and off-grid system builders, and anyone needing a dependable, serviceable way to isolate 12V battery power. If you require a compact, high-current isolation device that supports indicator wiring, resists rotation, and presents professionally when panel-mounted, this switch is a practical choice. It’s not a circuit breaker—use it for deliberate isolation rather than automatic overcurrent protection.