Blue Sea 7146 187 - Series Thermal Circuit Breaker - 120Amp

The Blue Sea 7146 187-Series Thermal Circuit Breaker – 120Amp is the backbone of reliable electrical protection for serious boaters and anglers who demand dependable power management on the water. This surface-mount thermal circuit breaker combines switching and circuit protection into a single, compact device—eliminating the need for separate components and saving valuable panel space in confined engine rooms and helm stations. Whether you're running a saltwater charter, a weekend fishing expedition, or extended liveaboard cruising, this breaker protects your vessel's critical electrical systems from overload damage and fires.

Built to meet SAE J1171 standards for marine electrical safety, the Blue Sea 7146 uses thermal sensing technology to automatically disconnect circuits when amperage exceeds the 120-amp rating, protecting everything from trolling motor circuits to cabin lighting and navigation electronics. The robust construction handles the thermal cycling, vibration, and corrosive salt-air environment that destroys inferior breakers within a season. Its compact footprint—just 4 x 2 x 5 inches—allows integration into tight spaces without compromising accessibility, while the manual switching function lets you isolate circuits for maintenance or emergency shut-down when needed.

This 120-amp breaker is ideal for high-draw applications such as main panel protection, windlass circuits, or large battery bank charging systems on vessels 35 feet and larger. Installation requires standard panel cutout and direct wire connection; it works seamlessly with Blue Sea Systems bus bars and panelboards for a fully integrated electrical architecture. Anglers and boaters who've trusted Blue Sea for decades know that this level of engineering prevents catastrophic electrical failures when you're miles from the nearest dock—making the 7146 an essential investment in vessel safety and operational reliability.