BI 1203-S Isolator
Onboard systems usually consist of two or more batteries that function independently when powering the 12 or 24V consumers. These batteries require independent charging with reliable battery isolators or battery combiners.
Mastervolt offers several intelligent solutions:
Battery isolators for conventional systems with an alternator or battery charger and two or three batteries
Mastervolt’s BI battery isolators are based on conventional diode technology. The diode voltage drop (ca. 0.6 V) can be compensated for by adapting the output voltage of the connected charger or alternator. Mastervolt Mass battery chargers and Alpha Pro charge regulators are standardly equipped with automatic voltage drop compensation.
Compact and lightweight
The Mastervolt BI battery isolators are compact and fully solid-state, preventing wear. The weight varies from 580 to 1300 grams.
Robust and durable
Completely corrosion-proof material with aluminum heat sinks. The electronic components are encased in synthetic materials, the BI models have molded diode splitters.
Fast installation
The synthetic end plates feature connection lugs, the solid bolt connections with nuts and locking rings ensure easy installation.
| Weight: | 3.1 lb |
|---|---|
| Dimensions: | 9× 6× 4in |
| Manufacturer Part Number | 83012031 |
|---|---|
| Manufacturer Name | Mastervolt |
| Drop Ships Direct from vendor | no |
| Hazardous materials | no |
| Truck Freight | no |
| Exportable | yes |
| First Class Mail | no |
| Oversized | no |
| Remanufactured | no |
| Closeout | no |
| Prop 65 | no |
| Returnable | yes |
Get expert advice on product selection and custom requirements.
No reviews yet
Free Shipping
24/7 Support
Online Payment
Fast Delivery

At Gulf Coast Outfitters, it is our mission to outfit boaters with the highest-quality marine hardware and boat accessories.
© 2026 Gulf Coast Outfitters. All Rights Reserved. | Developed by Mediusware Ltd.
| Weight | - |
| Dimensions | - |
| Manufacturer Part Number | - |
| Manufacturer Name | - |
| Drop Ships Direct from vendor | - |
| Hazardous materials | - |
| Truck Freight | - |
| Exportable | - |
| First Class Mail | - |
| Oversized | - |
| Remanufactured | - |
| Closeout | - |
| Country Of Origin | - |
| Prop 65 | - |
| Returnable | - |
| Google Merchant Category | - |