High-Capacity Dual Battery Management for Marine and Vehicle Systems

The Blue Sea HD-Series Battery Selector Switch is engineered to manage high-amperage power distribution in marine, RV, and heavy-duty vehicle applications. As part of the 500A HD-Series, this switch provides a robust solution for switching between two isolated battery banks or combining them for emergency starting power. Its rugged construction ensures reliability in demanding environments, making it an industry-standard choice for upgrading 12V and 24V electrical systems.

Versatile 4-Position Switching

Designed for flexibility, the 4-position dial allows you to select between Battery 1, Battery 2, or Both (1+2), as well as a complete OFF position. This functionality is essential for dual-battery setups, allowing you to reserve one bank for engine starting while powering accessories from the second bank. In the event of a flat starting battery, the "Combine" function allows you to parallel both banks for a powerful emergency jump-start.

Crucially, the switch features a make-before-break contact design. This ensures that power flow remains uninterrupted when switching between battery banks, preventing nuisance resets of sensitive electronics like GPS units, radios, and engine control modules.

Heavy-Duty Performance for High-Load Engines

Built to handle the demands of large diesel engines and high-draw electrical loads, this switch offers impressive power handling capabilities. While designated as part of the 500A series, it is rated for a solid 400A continuous current and an exceptional 1600A cranking rating (30 seconds). This high cranking capacity makes it suitable for starting large marine inboards and commercial vehicle engines without voltage drop issues.

Safety and Durability in Harsh Conditions

Safety is paramount in marine installations. This unit is ignition protected, making it safe for installation on gasoline-powered boats by preventing sparks that could ignite fumes. The case is constructed to withstand vibration and environmental stress, featuring tinned copper studs for maximum conductivity and corrosion resistance.

For installation flexibility, the switch supports both surface and rear panel mounting. The heavy-duty 1/2" (approx. M12) terminal studs are designed to accept large cable lugs, accommodating up to 4/0 AWG (approx. 120mm²) battery cables to minimise resistance and heat build-up.

Key Features

• High Cranking Rating: Handles up to 1600A for 30 seconds, ideal for starting heavy engines.
• 4-Position Selector: Offers OFF, 1, 2, and 1+2 (Combine) settings for complete battery management.
• Make-Before-Break: Allows switching between banks without cutting power to connected devices.
• Ignition Protected: Safe for use in engine rooms and fuel storage areas.
• Flexible Mounting: Compatible with surface or rear panel installation using 1/4" (approx. M6) fasteners.
• Corrosion Resistant: Features 1/2" (approx. M12) tinned copper studs for long-lasting marine performance.

Upgrade Your Power System

Ensure your vessel or vehicle has the reliable power switching it needs. Install the Blue Sea HD-Series Selector Switch today for safe, efficient, and professional battery management.