The Victron Quattro-II 2x120V is a 3kVA inverter/charger with two AC inputs, built for North American RVs and boats with 50A 120/240V shore power. It can connect to shore power and a generator at the same time and switch between them automatically. Here’s what Victron’s Quattro-II 3kVA 2x120V datasheet says.
Victron Quattro-II: Specs
| 12/3000/120-50 2x120V | 24/3000/70-50 2x120V | |
|---|---|---|
| Continuous power (25°C) | 3,000VA / 2,400W | 3,000VA / 2,400W |
| Continuous power (40°C) | 2,200W | 2,200W |
| Peak power | 5,500W | 5,500W |
| Max charge current | 120A | 70A |
| DC input range | 9.5–17V | 19–33V |
| Max efficiency | 93% | 94% |
| Zero load / AES / Search | 15W / 10W / 4W | 11W / 8W / 4W |
| AC inputs | Split-phase 180–280V or single-phase 90–140V; 50A per leg | same |
| Transfer switch | 50A | 50A |
| Auxiliary output | 50A per leg | 50A per leg |
Source: Victron Quattro-II 3kVA 2x120V datasheet.
How the 2x120V Design Works
- On shore power, it accepts 120/240V split phase (or 120V single phase) and passes it through to two output lines, L1 and L2.
- When inverting, it produces 120V single phase and feeds it to both L1 and L2, so loads on either leg keep running. It doesn’t produce 240V from the battery.
- Charging power is drawn from L1.
- PowerControl and PowerAssist work on the L1 input.
- Transfer time is under 20ms on L1, while L2 takes about 40ms, according to Victron.
Other Features
- Two AC inputs with automatic switching, for shore power plus a generator.
- Auxiliary output that’s live only on AC input, for things like a water heater.
- Parallel and three-phase operation, up to 6 units in parallel.
- Programmable relay and a VE.Bus port for a Cerbo GX, Ekrano GX or VRM.
- IP22, fan-cooled, rated -40 to +65°C.
Who It’s For
- 50A RVs and boats with a 12V or 24V bank and loads up to about 2,400W continuous.
- Generator plus shore power setups that want automatic input switching.
Good to Know Before You Buy
- No 240V output when inverting, so 240V appliances run only on shore power or a generator.
- 3kVA only. For more power, the classic Quattro 120V goes to 5kVA and 10kVA.
- No 48V model in the 2x120V datasheet.
Full specifications for the Quattro-II 2x120V are on Victron’s product page.
Worked Example: Battery Current and Bank Size
The Quattro-II’s 3,000VA rating translates into large DC currents, which drive your cable, fuse and battery choices. Here’s the math for a full 2,400W load, using the datasheet’s 93% (12V) and 94% (24V) peak efficiencies:
| System | Load | DC current (estimate) |
|---|---|---|
| 12/3000/120 | 2,400W | 2,400 ÷ 12V ÷ 0.93 ≈ 215A |
| 24/3000/70 | 2,400W | 2,400 ÷ 24V ÷ 0.94 ≈ 106A |
| 12/3000/120 | 1,000W (microwave) | ≈ 90A |
Worked estimates. Battery voltage sags under load, so real current runs a little higher.
That’s why many 50A RV builds move to 24V: the same power at roughly half the current means thinner cable and smaller fuses. Size the cable and DC fuse from the table in the Quattro-II manual.
Bank size: to run a 1,500W load for two hours you need about 3,000Wh, plus inverter losses, so roughly 3,200Wh. That’s about 250Ah of usable capacity at 12.8V, or about 125Ah at 25.6V. LiFePO4 banks let you use most of their rated capacity, so a 300Ah 12V bank or a 150Ah 24V bank covers this with some reserve.
Worked Example: Recharge Time
On shore power, the 12V model charges at up to 120A and the 24V model at up to 70A.
- A 400Ah 12V LiFePO4 bank at 20% needs about 320Ah. At 120A that’s roughly 2.7 hours of bulk charging, plus a short absorption phase.
- A 200Ah 24V bank at 20% needs about 160Ah. At 70A that’s roughly 2.3 hours, plus absorption.
Estimates. Charging power comes from L1, so a heavily loaded L1 leg leaves less for the charger.
Using Two AC Inputs: Shore Power and a Generator
The Quattro-II has two AC inputs and switches between them automatically. A common layout is to wire the generator to one input and the 50A shore inlet to the other. In the configuration you then set a separate input current limit for each source:
- Shore power: set the limit to the pedestal breaker. At a 30A campground post, set 30A so the Quattro-II never trips it.
- Generator: set the limit a little below the generator’s continuous rating. A 3,500W 120V generator delivers about 29A, so a limit of about 25A leaves headroom.
With PowerAssist on, the Quattro-II tops up from the battery when your loads go above that limit, so a small generator or a weak shore post can still run a bigger load for a while.
Setup Steps
- Plan the battery bank and DC wiring from the manual’s cable and fuse table, with the fuse close to the battery.
- Wire the AC inputs (shore power and generator) and the AC output to your RV or boat panel. Use a licensed electrician for the AC side.
- Connect the battery last, then switch the Quattro-II on.
- Configure it with VictronConnect through an MK3-USB interface, or remotely through a GX device. Set the battery type and charge voltages, both input current limits and PowerAssist.
- Add monitoring. A Cerbo GX or Ekrano GX on the VE.Bus port shows both inputs, the battery and the loads, and links the system to the free VRM portal.
- Test each source: unplug shore power, start the generator and watch the transfer, then try running on the inverter alone.
FAQ
Does the Victron Quattro-II make 240V?
Not from the battery. It passes through 240V split phase from shore power, but inverts 120V single phase.
Quattro-II or MultiPlus-II 2x120V?
Pick the Quattro-II if you need two AC inputs, such as shore power and a generator.
Can I run two Quattro-II units together?
Yes. The datasheet lists parallel and three-phase operation, with up to six units in parallel for more power.
Which battery voltage should I choose?
For loads near the full 2,400W, 24V halves the DC current compared with 12V. If your RV already has a 12V system and lighter loads, the 12V model with its 120A charger is the simpler fit.
What does the auxiliary output do?
It’s live only when an AC input is connected, so loads like a water heater run on shore or generator power and switch off automatically when you’re on the inverter.
Do I need a GX device?
It’s optional. The Quattro-II works on its own, and a Cerbo GX or Ekrano GX adds a touchscreen, remote settings and VRM monitoring.
Sources: Victron Quattro-II 3kVA 2x120V datasheet; product page, victronenergy.com, accessed Oct 2026.
Related: Allwei 1500W Pure Sine Wave Inverter Review, Pro Chaser 400W Car Power Inverter Review, EcoFlow Delta 3 Max Van Life Leisure Battery, plus the Victron Energy Guide