Charging via Generator (With Victron Power Assist)

Overview
If you’re off-grid and shore power isn’t available, a portable generator is your next best option to charge the caravan. The Victron MultiPlus-II Inverter/Charger will automatically detect the generator input and begin charging the battery — but to avoid generator stalling, you must set the system up correctly using Power Assist.

1. Generator Type: Bonded or Floating Neutral

The Victron MultiPlus-II Inverter/Charger is designed to work with both bonded and floating neutral generators.

  • The system automatically detects the generator’s AC input type and adjusts its internal configuration to ensure:
    • Proper grounding
    • Safe operation of RCDs (Residual Current Devices, also known as ground fault protection)

There’s no need to manually bond the neutral or modify your generator — the system handles it internally for safe and correct operation.

However, if a fault is shown (e.g. no earth or RCD tripping), this may indicate:

  • A wiring issue with the generator plug
  • An incompatible generator model or poor grounding on the generator frame

When in doubt, consult your Harvok technician or the Victron MultiPlus-II manual.

2. Why Generators Stall — and How to Prevent It

Generators may stall if the caravan draws more current than the generator can supply.

Example:
A 3000VA (3kVA) generator typically supplies up to 12 Amps. If your van tries to pull 15A or more (e.g. with air conditioning + microwave), the generator may overload and shut off.

3. Victron Power Assist: Seamless Support

The Power Assist feature in your Victron MultiPlus-II prevents stalling by intelligently blending generator and battery power.

How it works:

  • You set a safe AC input limit (e.g. 11A for a 3kVA generator).
  • The inverter will only draw 11A from the generator.
  • If you use more than 11A in the van (e.g. 20A), the inverter supplies the extra 9A from the battery.
  • This prevents overload while still powering your appliances.

4. How to Set the Generator Input Limit (AC Input)

Caution: Only adjust these settings if you’re confident, or consult a Harvok technician.

To change the AC input limit:

  1. Go to your Victron Digital Multi Control panel.
  2. Use the rotary knob to select a current limit (e.g. 10A or 11A).
  3. The new limit controls how much current the system will draw from the generator.

5. General Setup Instructions

To charge your van with a generator:

  1. Start the generator and let it warm up (2–3 minutes).
  2. Plug a 15A power lead from the generator into the caravan’s driver-side power inlet.
  3. Ensure the AC Input Limit is correctly set.
  4. The Victron inverter will switch to charging mode and begin supplying 240V AC to appliances.
  5. If more power is needed than the generator can provide, Power Assist will supplement with battery power automatically.

Generator Sizing Recommendation

  • Minimum Capacity: 3000VA (3kVA) recommended
  • Must output pure sine wave, 230–240V AC, 50Hz

Technical Reference

  • Inverter Model: Victron MultiPlus-II 48/3000/35-50 230V
  • Max Charge Rate: 30A at 48V
  • Compatible Input: Shore power or neutral bonded generator

📘 Victron MultiPlus-II Inverter/Charger Manual (AU Model)📘 Victron Digital Multi Control – Operating Manual