Blue Sea E Series Battery Switch 4 Position Selector

The Blue Sea Systems E-Series Battery Switch is a heavy-duty marine battery isolator designed for inboard petrol and diesel engines, offering reliable battery isolation and switching for demanding marine electrical systems. With a 350A continuous rating, 45% higher than many standard battery switches, it is built to handle high current loads while meeting stringent marine safety standards.

Featuring a make-before-break contact design, the 9001E and 9002E allows seamless switching between battery banks without interrupting power to essential onboard electronics. Its ignition-protected construction makes it safe for installation aboard petrol-powered boats, while the IP66-rated housing provides excellent protection against water ingress and harsh marine conditions.

Manufactured with tin-plated copper studs for maximum conductivity and corrosion resistance, the switch accepts 4/0 AWG battery cables and multiple cable terminals thanks to its extended 7/8" (22mm) terminal studs. The one-piece terminal stud design ensures the terminals remain secure throughout the life of the switch, while tactile knob indicators allow the switch position to be identified by touch alone.

For maximum installation flexibility, the 9001E and 9002E support surface or rear panel mounting and fit the mounting hole patterns used by many Perko® and Guest® low-amperage battery switches, making it an excellent upgrade or replacement.

The 9002E is equipped with a Alternator Field Disconnect (AFD) providing additional protection for your charging system by safeguarding the alternator's diodes if the battery switch is accidentally turned to the OFF position while the engine is running. Where alternator protection is not required, the AFD terminals can instead be used to connect an LED indicator, allowing the LED to illuminate whenever the battery switch is in any position other than OFF. This provides both increased installation flexibility and a convenient visual indication that the battery system is active.

• Heavy-duty marine battery switch
• 350A continuous current rating
• 45% higher continuous rating than many standard battery switches
• Designed for inboard petrol and diesel engines
• Make-before-break contact design prevents power interruption during switching
• Ignition protected for petrol-powered boats
• Optional Alternator Field Disconnect (AFD) on applicable models protects alternator diodes
• AFD terminals can also be used to power an LED status indicator
• Tin-plated copper studs for maximum conductivity and corrosion resistance
• One-piece terminal stud design prevents loosening
• Accepts 3/8" (M10) ring terminals
• Compatible with 4/0 AWG battery cables
• Surface or rear panel mounting
• Fits Perko® and Guest® low-amperage battery switch mounting patterns
• Tactile knob position indicator
• International symbol labelling
• IP66 waterproof protection
• CE marked and UL Listed
• Meets ABYC, ISO 8846, UL1500 and SAE J1171 requirements