Mastervolt - Battery Isolators 1203-S
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Master Your Onboard Power with Mastervolt Battery Isolators
Ensure seamless and efficient battery management on your boat with Mastervolt's BI series battery isolators. These compact and robust devices prevent unwanted battery drain, safeguarding your electrical system and maximizing your time on the water.
Intelligent Battery Management
- Prevents battery drain: Isolates your batteries, ensuring your starting battery remains fully charged and ready to start your engine, even if other onboard systems have depleted the secondary battery.
- Promotes independent charging: Allows independent charging of multiple batteries, optimizing the performance and lifespan of your batteries.
Reliable and Efficient
- Conventional diode technology: Proven and reliable design, with minimal energy loss for efficient power distribution.
- Automatic voltage drop compensation: Compatible with Mastervolt chargers and regulators, automatically adjusting for voltage drop to ensure proper battery charging.
Built to Withstand the Marine Environment
- Compact and lightweight: Easy to install and integrate into your boat's electrical system.
- Robust construction: Corrosion-resistant materials and encapsulated electronics ensure long-lasting performance in harsh marine conditions.
- Fast and easy installation: Equipped with connection lugs and solid bolt connections for a straightforward installation process.
Key Highlights
- Prevents battery drain and protects your starting battery
- Enables independent charging of multiple batteries
- Conventional diode technology with minimal energy loss
- Automatic voltage drop compensation (with compatible chargers/regulators)
- Compact, lightweight, and easy to install
- Robust construction for durability in marine environments
Shipping
We ship worldwide from the United States. Rates are calculated at checkout based on destination and package weight. Some items include free shipping, which will show automatically. Not every product is eligible for international shipping; checkout will confirm eligibility. We do not ship to PO Boxes except through USPS, and not all packages qualify.
Processing and dispatch
Most orders are verified, packed, and handed to the carrier within 1 to 2 business days. Some products may need extra handling time or ship directly from the manufacturer. For certain international orders, inventory transfers between warehouses may add time. If any delay is expected, we will let you know the dispatch date.
Delivery and tracking
Deliveries are handled by trusted carriers such as USPS, UPS, FedEx, and DHL. Estimated arrival times appear at checkout and depend on your location and the service you choose. These are estimates and can be affected by customs or carrier disruptions. A shipping confirmation with a tracking link is emailed when your order ships, and tracking may take up to 24 hours to update. You can also view tracking in your account.
Duties, taxes, and support
International customers are responsible for any customs duties, taxes, and fees charged by the destination country. If these charges are refused and a shipment returns to us, the carrier’s return cost and any re-entry customs fees will be deducted from the refund. If your order is late or you need help, contact cs@qualityboatparts.com and we will assist you.
Quality Boat Parts is a reseller. Many items include a manufacturer’s warranty, and all warranty service is handled directly by the manufacturer. We do not manage or administer warranty claims on behalf of customers.
Warranty terms, coverage, and duration are set by each manufacturer. Issues involving defects, repairs, or replacements must be addressed with the manufacturer’s support team. When available, the warranty period is listed on the product page. If it is not shown, contact us or the manufacturer for details before purchasing.
To start a claim, the customer must contact the manufacturer and follow their process. Keep your proof of purchase and original packaging, and register the product if the manufacturer requires it, as these are often needed for warranty service.
We are happy to help you find the right contact or documentation, but we cannot decide outcomes or intervene in claim resolutions. For guidance, email cs@qualityboatparts.com.