A battery compartment has several jobs: disconnecting power, protecting cables against faults, supplying individually fused accessories and, sometimes, feeding an inverter or charging a second battery bank. These functions use different components. This RV DC power-distribution map shows how the roles fit together, then links to exact fuse holders, switches, busbars, relays and inverter-protection products in NewRVParts.
Three different power paths around an RV battery bank
The drawings are separated intentionally. A high-current inverter cable should not be confused with a row of small accessory fuses, and an automatic charging relay is not a substitute for a source-side protection device.
Individual accessory circuit fuses are downstream of the protected feed. The fuse block's maximum current and wire ratings still apply.
The chosen fuse amperage depends on the inverter, cable size, battery-bank fault current and system voltage; it is not determined by the diagram.
Both ACR battery leads require suitable protection and installation controls. A battery-combining relay is not a DC-DC charger; verify charging compatibility and battery chemistry.
Where does a common busbar fit?
Negative returns from multiple DC loads can be collected on a properly rated negative busbar before returning to the battery negative. A common busbar may also be used for appropriately protected positive distribution, but it does not provide individual circuit fusing. The Blue Sea 2301 is one example; keep positive and negative conductors clearly identified.
What each component does
| System role | Catalog example | Important distinction |
|---|---|---|
| Source-side fuse | MRBF 2151 | Two fused output positions; 300A maximum overall. Select fuses separately. |
| Battery isolation | Dual Circuit Plus 5511e | OFF / ON / COMBINE for two battery-load circuits; not a voltage-sensing relay. |
| Accessory protection | ST Blade 5025 | Six ATO/ATC circuits, 30A per branch and 100A maximum per block. |
| Return/distribution bus | Blue Sea 2301 | 10 #8-32 terminals, two 1/4-inch studs; 150A continuous DC. |
| Inverter cable protection | Go Power FBL-300 / 44227 | 300A Class T fuse and covered block supplied together; not a universal inverter fuse rating. |
| Dual-bank charging | m-ACR 7601 | 65A automatic charging relay connects eligible banks when charging voltage is detected. |
Matching components and product photos
These catalog cards are linked to the exact manufacturer-numbered NewRVParts listings. Prices and warehouse availability are shown on the product pages. Products ship from supplier warehouses; there is no in-person viewing or pickup.
Detailed diagrams for choosing the right part
Manufacturer installation references
Blue Sea publishes the 2151 MRBF holder diagram, 5511e switch drawings, 5025 branch-fuse instructions and 2301 busbar dimensions. Go Power provides the Class T fuse-block kit specifications. Always follow current instructions for the exact supplied hardware.
How solar and shore-power chargers fit into the battery system
A solar charge controller, a converter and an inverter/charger all have different inputs and installation requirements. Each can provide a charging path when correctly installed; none is a substitute for the circuit protection in the diagrams above. These are separate functional examples, not instructions to connect all three devices together.