The Electrical Architecture: Dual Battery, 80A Limit, and No Vampire Taps
The Electrical Architecture: Dual Battery, 80A Limit, and No Vampire Taps
Main and auxiliary battery positions, charging current limits, prohibited connection methods, cable selection rules, and the ground bolt constraints every builder must know.
The electrical system requires precise installation and adherence to current limits. Many builders create failures that are difficult to diagnose after the fact.
The Battery Architecture: Dual System, Single Charging Path
The main battery is under the rear seat bench. An additional 12V battery is also under the rear seat bench, positioned next to the main battery. Maximum charging current for additional batteries is 80A total, including any charging current limiter.
Auxiliary Battery Rules
- Maximum charging current: 80A total across all auxiliary batteries
- Charging current limiter required for parallel connection
- Batteries may only be charged with INEOS-approved smart charger
- Positive and negative terminals must be disconnected during charging
- Battery must be disconnected if vehicle unused >1 week
The Prohibition on Vampire Taps
Do not use insulation-piercing connectors. Do not twist wires together. Do not solder directly to existing wiring. When the insulation pierces, it exposes the copper to the environment. Corrosion begins immediately. The contact resistance increases. Months later, you have an intermittent fault you can't trace.
Cable Selection: Cross-Section Matters
| Max Continuous Current | Fuse Rating | Minimum Cable Cross-Section |
|---|---|---|
| 0–4.0 A | 5 A | 0.35 mm² |
| 4.0–8.0 A | 10 A | 0.75 mm² |
| 9.0–16 A | 20 A | 1.0 mm² |
| 17–24 A | 30 A | 2.5 mm² |
| 25–32 A | 40 A | 4 mm² |
| 33–40 A | 50 A | 6 mm² |
| 41–56 A | 70 A | 10 mm² |
| 57–80 A | 100 A | 16 mm² |
| 81–100 A | 125 A | 25 mm² |
| 101–120 A | 150 A | 35 mm² |
Use lead-free PVC-sheathed cables with insulation limiting temperature greater than 105°C. Cables near the exhaust must be sheathed in high-temperature resistant material.
Ground Bolts: The 3-Lug Limit
Maximum three cable lugs per ground bolt. Safety system ground bolts cannot be used for additional attachments. More than three lugs on a single bolt creates a joint that doesn't torque properly.
Regulatory Compliance
All installed electrical equipment must comply with UN-R 10 and bear CE mark. Do not change factory fuse ratings. The ratings are calculated based on wire sizes in the original harness.