Blue Sea Systems 187 Series Surface Mount DC Circuit Breaker

The Blue Sea Systems 187 Series Surface Mount DC Circuit Breaker is a heavy-duty, marine-rated breaker. It gives you circuit protection and a manual on/off switch in one device. It is built on Bussmann 187-series breaker technology. It suits high-current DC circuits such as battery feeds, windlasses, thrusters, inverters and other large loads on boats, RVs and other DC systems.

Key Features:

• Switch and protection in one: A single lever turns the circuit on and off by hand and also trips under overload.
• Trip-free design: The breaker cannot be held on during a fault.
• Clear status indication: A large, bright lever can be mounted vertically or horizontally and shows at a glance whether the breaker is on, off or tripped.
• Ignition protected: Meets SAE J1171 external ignition protection requirements. It is safe to install aboard gasoline-powered boats.
• Waterproof construction: A sealed thermoset polyester case is designed for damp marine environments.
• Surface mounting: The breaker screws directly to a bulkhead or panel. It has recessed mounting holes for a clean appearance and front-facing wire connections.
• Heavy-gauge wiring: Robust 5/16-inch (M8) terminal studs allow high-torque connections. Large clearance around the studs accepts heavy-gauge cable lugs.
• Thermal operation: A thermally responsive bi-metal blade senses overload.

For a safe, code-compliant installation, cover the terminals with insulating boots or cable caps. ABYC standards call for this. Use cable lugs sized for the 5/16-inch studs. Choose the amp rating that matches your wire gauge and load.

Blue Sea Systems is a respected name in marine and RV electrical products. The 187 Series is a durable option for dependable DC circuit protection and switching.