System Energy Budgets & Vehicle Upgrades
Holistic power planning tools for complete campervans, overland touring rigs, high-output automotive alternators, and mobile audio systems.
Complete Audit
Campervan Electrical System Budgeter
Interactive 24-hour appliance energy audit calculator that recommends balanced battery capacity, solar panel wattage, and DC-DC alternator charging rates.
Overland 4WD
Overland 4WD Dual-Battery System Sizer
Balances auxiliary 12V fridge runtimes against daily driving hours to size secondary under-bonnet or canopy batteries and DC-DC chargers.
Automotive
Big 3 Automotive Wiring Upgrade Sizer
Sizes primary heavy-gauge cables between alternator, battery, and chassis ground to eliminate voltage sag from high-power accessories.
Car Audio
Car Audio Power & Cable Sizing Tool
Evaluates RMS amplifier wattage, amplifier class efficiency, and music dynamic crest factors to select power wire gauge and battery fuses.
Aux Lighting
Off-Road LED Light Bar Relay/Harness Sizer
Sizes automotive SPST relays, main 12V power harnesses, inline blade fuses, and switch trigger wiring for high-lumen off-road light bars.
Marine Deck
Marine Anchor Windlass Cable Sizer
Size long bow-to-stern battery cables for 12V and 24V anchor windlasses (700W to 2000W) using ABYC intermittent 10% voltage drop rules and thermal breaker sizing.
Towing & RV
Trailer 7-Pin Aux Charging Line Sizer
Diagnose voltage drop across factory 7-pin trailer wiring (Pin 4) and compare dedicated Anderson charge lines vs in-trailer DC-DC chargers.
RV & Marine Plumb
12V Fresh Water Pump Wire & Fuse Sizer
Size wiring, fuse protection, and pressure switch circuits for diaphragm fresh water pumps (1.5 to 5.5 GPM) accounting for startup motor inrush.
Ventilation
RV Roof Vent Fan Runtime & Energy Sizer
Calculate daily amp-hour consumption and multi-speed power draw for MaxxFan and Fantastic Fan 12V ventilation units across battery chemistries.
Off-Road Recovery
Electric Winch Battery Draw & Cable Sizer
Calculate heavy stall current (up to 450A+), cable voltage sag, and dual-battery capacity requirements for 8,000 lb to 12,000 lb recovery winches.
Heating Diagnostics
Diesel Heater Glow Plug Voltage Drop Sizer
Troubleshoot E-01/E-02 low voltage startup lockout errors on 12V and 24V diesel heaters by modeling glow plug inrush current against cable and fuse resistance.
DOT Road Safety
Trailer Breakaway Battery & Charge Sizer
Calculate electric brake magnet current draw, verify mandatory DOT 15-minute emergency lockup compliance (49 CFR § 393.43), and determine 7-pin recharge time.
Marine Maneuver
Marine Bow Thruster Cable & Duty-Cycle Sizer
Size 12V and 24V bow and stern thruster cables to prevent contactor solenoid chatter (< 10.5V), evaluate thrust loss, and compare forward bow battery tradeoffs.
Refrigeration
12V DC Compressor Fridge Power Calculator
Model real-world daily Amp-hour (Ah/day) and Watt-hour (Wh/day) consumption across varying ambient temperatures, freezer modes, and solar battery sizing.
Marine Propulsion
Trolling Motor 24V & 36V Wiring & Thrust Sizer
Size marine battery cables, ABYC manual-reset circuit breakers, heavy-duty disconnect plugs, and calculate multi-speed battery runtimes across 30 to 112 lbs of thrust.
Holistic Mobile Power Architecture & System Integration
A reliable mobile electrical installation cannot be engineered as isolated components. Energy generation, storage, and distribution must be harmonized into an integrated system:
- Energy Balance Equilibrium: Over any 24-hour cycle, total energy generation (solar PV harvest + driving alternator DC-DC charge + shore power replenishment) must exceed total appliance consumption plus inverter and conversion losses:
Mobile Energy Balance Equation $$E_{\text{generation}} \ge \frac{E_{\text{loads}}}{\eta_{\text{system}}} + E_{\text{quiescent}}$$If daily demand exceeds replenishment, the battery bank enters a compounding deficit cycle, resulting in premature low-voltage disconnects.
- Smart Alternators & DC-DC Charging: Modern vehicles utilize smart ECU-controlled alternators (Euro 6 / variable voltage) that drop charging voltage to 12.2V when the starter battery is satisfied, completely halting charge flow to an auxiliary house battery. Dedicated DC-DC chargers are essential to boost and regulate voltage into a multi-stage charging profile tailored to lithium or AGM house banks.
- Vehicle Chassis Ground vs. Dedicated Copper Return: Stamped automotive sheet metal has higher resistivity than copper conductor and suffers from high joint resistance across welded seams and paint coatings. For high-current DC loads exceeding 30A (such as inverters, winches, and high-output DC-DC chargers), a dedicated negative copper return cable run directly to the battery or central negative busbar is required to prevent ground-loop voltage drop and sensor interference.
- The "Big 3" Electrical Upgrade: High-amperage auxiliary loads, audio amplifiers, and secondary charging systems require upgrading the three primary vehicle cables: alternator positive to starter battery, engine block to chassis ground, and battery negative to chassis ground. Upgrading these factory conductors eliminates headlights dimming and stabilizes system operating voltage.