Blue Sea 3002 HD Battery Switch

Blue Sea 3002 — Heavy-Duty Battery Selector Switch

Classic four-position battery selector switch for dual-battery van, RV, and marine builds. Manual control over which battery (or both) is powering your loads.

Key Features

• 4 positions: OFF / Battery 1 / Battery 2 / Both
• 350A continuous, 700A intermittent rating
• Alternator field disconnect (optional wiring) protects alternator when switch is turned off
• Surface mount with red handle for visibility
• UL-recognized and marine-rated

Use Cases

• Dual-battery van builds: isolate starter battery from house bank when parked
• Emergency kill switch: one-motion shutoff of all DC electrics
• Service mode: disconnect the entire system when working on wiring

Designing a dual-battery system? Use our free System Build Helper to plan your starter-plus-house electrical layout, including where the selector switch fits.