Newmar 2-3-70A Isolator 2AIT 3BATT 70AMP

Upgrade your power management setup with a robust solution designed for demanding environments like marine vessels, RVs, and heavy-duty trucks. This isolator seamlessly handles charging from dual alternators to support three separate battery banks, ensuring each one gets precisely what it needs without risking cross-discharge or overcharging mishaps.

Why Choose This Heavy-Duty Battery Isolator?

In setups with multiple batteries—think house, engine start, and auxiliary banks—keeping charging efficient and safe is crucial. Traditional single-alternator systems often fall short when scaling up, leading to uneven charging or parasitic drains. This unit steps in as a smart intermediary, using high-quality diodes to create isolated paths. Alternator output flows freely to all banks during charging, but reverse flow is blocked when engines are off. Result? Longer battery life, reliable starts, and peace of mind on long hauls or offshore adventures.

Built to thrive in harsh conditions, it shrugs off corrosion with its anodized aluminum housing and pairs with stainless steel hardware for mounts that last. Whether you're retrofitting an older boat electrical system or optimizing a custom van build, this isolator delivers continuous performance without the fuss of relays or complex electronics.

Key Advantages Over Basic Isolators

• Versatile Voltage Handling: Perfect for 12V to 48V negative ground systems, adapting to everything from standard automotive to high-voltage industrial apps.
• Dual Alternator Ready: Maximizes output from twin setups common in larger engines, boosting charge rates without overload.
• Three-Bank Isolation: Independently manages starter, house, and thruster batteries, preventing one from draining into another during downtime.
• Low Maintenance Design: No moving parts means fewer failures; just mount vertically for best heat dissipation and let it run.
• Terminal Protection: Snap-on covers shield connections from shorts, moisture, and accidental contact—essential in wet or dusty environments.

How It Works: Simple, Effective Charging Logic

Connect your alternators to the input terminals and batteries to the outputs. When the alternator voltage rises above each battery's level (typically by 0.7-0.9V), current flows through the diodes to charge. Batteries with lower charge states pull more amps naturally, self-balancing the load. Once fully charged, flow tapers off, avoiding gassing or heat buildup. It's passive, automatic, and draws zero power when idle—ideal for fuel-conscious operators.

Pro tip: Pair it with smart alternators or temperature sensors for even finer control, but it shines standalone in most stock configurations.

Real-World Applications

Marine: Isolates engine start from house loads on yachts or fishing boats, keeping radios and nav gear powered without starter battery risk.
RV & Overlanding: Manages chassis, coach, and inverter batteries for off-grid boondocking.
Commercial Fleets: Ensures backup power in trucks or service rigs, reducing downtime from dead starts.

Users rave about its reliability in extreme temps—from Alaskan winters to desert summers—proving it's not just tough, but thoughtfully engineered.

Performance at a Glance

Quick install note: Use appropriately sized cables (at least 4 AWG for 70A) and fuses near batteries. Avoid self-exciting alternators, as they can cause issues—double-check your setup with the alternator specs.

Frequently Asked Questions