Sea-Dog 4227901 Smart Dual Battery Isolator, 12V
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You have 30 days to request a return. All sale items are final sale.
Sea-Dog Smart Dual Battery Isolator (12V) is designed to help manage dual-battery charging while isolating batteries to protect the starting battery. It automatically engages and disengages based on pre-set voltage thresholds and includes a visible LED status indicator.
Key Features
- Automatically charges two batteries and then isolates them to help ensure the starting battery remains ready for use
- Engages/disengages the circuit at pre-set voltages by sensing input voltage
- Cut-in voltage: 13.3V
- Cut-out voltage: 12.8V
- Surge protected
- LED indicator shows when the unit is engaged
- Machined brass construction
- Weatherproof injection molded nylon housing
- Durable silver-tipped contacts
- Includes hardware for installation: two #8 RH fasteners
- IP65 rated for weather resistance
Product Compatibility
- Dual battery charging management for 12V marine systems
- Boat battery setups requiring automatic isolation to help protect starting batteries
- Applications where a weather-resistant dual battery isolator/ACR is needed
Product Details
- Sea-Dog Smart Dual Battery Isolator, 12V
- Model/SKU: 4227901
- Voltage: 12V
- Cut-in voltage: 13.3V
- Cut-out voltage: 12.8V
- Rated amperage (as listed in Sea-Dog catalog): 140A
- IP rating: IP65
- Construction: machined brass with weatherproof injection molded nylon housing
- Contacts: durable silver tipped contacts
- Fasteners: installs with two #8 RH fasteners (included)
- LED indicator: alert when unit is engaged
Parts Desk Insights
Best Use Case: Best suited for dual-battery installations that need automatic charge control while helping keep the primary starting battery isolated from house draw.
Common Issues: If the LED status never changes as expected, double-check that battery wiring matches the intended starting vs. auxiliary sides and that the isolator is receiving the correct sensed voltage at its input. For weatherproof installs, verify mounting and cable connections are sealed/secured appropriately around the housing to maintain the IP65 rating.
Related Products & Accessories
- Battery Isolators & ACRs - Browse the Battery Isolators & ACRs collection for additional dual-battery management options.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.