Electrical8 min read
Class T vs MRBF Fuse for LiFePO4 (2026 Comparison)
Class T fuses (20,000 AIC) are the LiFePO4 gold standard. MRBF terminal fuses (10,000 AIC) cost 5-10x less. Compare specs, cost, install, and when each is acceptable.
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Our App Cable is now on iOS
Plan safe DC wiring on the go and sync with VoltPlan for full system design when you are back at your desk.
- Automatic cable sizing with built-in safety guardrails
- Real-time fuse and breaker recommendations
- Hand off projects to VoltPlan for detailed diagrams
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Android version coming soon
RV & Boat Electrical System Design12V Wiring Diagram Creator
Plan safe 12V wiring for your camper van, RV, boat, or off-grid build. Wire sizes, fuse ratings, and solar layouts are calculated for you — so you get it right the first time.
Start Your Wiring DiagramNo signup required • Free 12V wiring diagram creator • Export anytime
New companion app
Our App Cable is now on iOS
Plan safe DC wiring on the go and sync with VoltPlan for full system design when you are back at your desk.
- Automatic cable sizing with built-in safety guardrails
- Real-time fuse and breaker recommendations
- Hand off projects to VoltPlan for detailed diagrams
Download on the App Store
Android version coming soon
Free Forever for Personal Use
No Signup Required
Export Anytime
How It Works
From blank canvas to finished wiring diagram in minutes
Step 1
Choose a Template
Pick a starting point for your RV, boat, or off-grid project.
Step 2
Customize Your System
Add components, connect wires, and size your cables.
Step 3
Export and Share
Download your diagram or share a live link with your installer.
Choose Your 12V Wiring Diagram Template
RV Electrical System Design
Plan your RV's 12V system online with our free wiring diagram creator. Design complete camper electrical systems with solar panels in series or parallel, battery banks, and shore power connections.
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Marine Wiring Diagram Software
Design basic 12 volt boat wiring diagrams with our free marine wiring diagram software. Create complete marine electrical systems with proper DC wiring, battery switches, and navigation electronics.
Start Boat Wiring Diagram
Solar Panels in Series Diagram Creator
Design off-grid solar power systems with our 12V wiring diagram creator. Create solar panels in series diagrams, parallel configurations, and complete battery bank setups for cabins, tiny homes, and remote installations.
Start Solar DiagramFree 12V Wiring Diagram Software
Everything you need to design your electrical system online
RV Electrical System Design
Create complete RV wiring diagrams with our intuitive drag-and-drop interface. Design shore power connections, battery systems, and 12V distribution panels.
Marine Wiring Diagrams
Marine wiring diagrams for boats of any size. Plan your basic 12 volt boat wiring diagram with the right marine-grade components, wire sizes, and fuse ratings.
Solar Panel Configurations
Design solar panels in series diagrams or parallel configurations. Calculate optimal solar array sizing for your power needs.
12V Wiring Diagram Creator
Free online 12V wiring diagram creator with automatic wire sizing calculations and component validation.
For Developers: MCP Integration
Generate wiring diagrams programmatically with our open-source MCP server. Connect your AI assistant or automation tooling to VoltPlan via the Model Context Protocol.
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The Busbar
DC electrical news for campers, boats, and off-grid builds
A weekly roundup of inverter releases, BMS firmware updates, battery cell news, and product launches from the DC-power world. Same folks who build VoltPlan, curating what matters for people wiring real systems.
Read The BusbarRV & Marine Electrical Guides
Expert guides on RV electrical system design, 12V wiring diagrams, marine wiring, solar panel configurations, and off-grid power systems.
Electrical8 min read
Free 12V Electrical Calculators for Campers, Boats & Off-Grid (2026)
Five free online calculators for 12V, 24V, and 48V DC systems: wire gauge, fuse size, battery bank, inverter wattage, and solar array. No signup, metric and imperial, embed-ready.
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