Blue Sea Systems Battery Switch

Blue Sea Systems Battery Switches: Engineering You Can Trust Offshore and On the Road

When a boat's engine won't start 10 miles from the marina, the battery switch becomes the most important piece of hardware on board. Blue Sea Systems has built its reputation on exactly these high-stakes moments, engineering battery switches that perform reliably in the harshest marine, RV, and specialty vehicle environments. What separates Blue Sea Systems from the competition isn't just build quality — it's a level of standards involvement that few manufacturers can match.

With involvement on the American Boating Yacht Council (ABYC) Electrical Component Project Committee, Blue Sea Systems is close to the source of standards for battery switches. The company's participation in the process means quick response when standards and needs of boaters change. In practice, this means every Blue Sea Systems battery switch is designed not just to pass compliance checks, but to help write the playbook those checks are based on.

A Series for Every Application

Blue Sea Systems organizes its battery switch lineup into distinct series, each targeting a specific set of installation requirements and performance demands.

• HD-Series (Heavy Duty): The HD-Series delivers up to 600 Amperes continuous rating for large diesel engines, high power output, and low heat generation. It is ignition protected, safe for installation aboard gasoline-powered boats, and rated IP66 — dustproof and protected against heavy seas and jets of water from all directions. The HD-Series Selector switch features a make-before-break contact design that allows switching between battery banks without power interruption.
• e-Series: The e-Series offers a versatile family of On/Off and Selector switches, including the patented e-Series Dual Circuit Plus™ Battery Switch (Patent No. 7,442,887). These switches add the convenience of combined charging and starting circuits in a compact, panel-friendly footprint.
• m-Series (Mini): The m-Series switch is versatile enough to meet just about any battery switch application for small and medium-size boats. It is very compact, measuring less than 3" by 3", making it ideal for installations where there are size and space constraints. Despite its small footprint, these switches are capable of 300 Amperes continuous rating and 500/450 Amperes intermittent rating.

Dual Circuit Technology: Smarter Battery Management

The Dual Circuit™ and Dual Circuit Plus™ Battery Switches provide engine and start circuit isolation. They turn the House and Start batteries on at the same time but isolate them from each other, protecting the Start battery from being discharged by House loads like refrigerators, stereos, and lights. Battery isolation also protects sensitive electronics from voltage spikes and sags that may occur during engine starting. This intelligent design eliminates one of the most common causes of being stranded on the water — a dead start battery drained by overnight house loads.

Built to Standards, Backed by a Lifetime Guarantee

Blue Sea Systems develops and manufactures dependable AC and DC electrical products for marine and specialized vehicle applications, designed in the USA and engineered to excel in challenging environments. Industry involvement ensures products meet ABYC, NMMA, and Coast Guard standards. And Blue Sea Systems stands behind its products for as long as you own them, replacing or issuing a credit for any product found to be defective in materials or manufacture.

Whether you're outfitting a center-console fishing boat, a cruising sailboat, or an expedition RV, a Blue Sea Systems battery switch is one of the most important reliability upgrades you can make to your electrical system.