Marsun MVD8 7.5 kW Three-Phase Diesel Generator with AVR and Two-Wire Start

The Marsun MVD8 is a three-phase diesel generator rated at 7.5 kW continuous and 8 kW maximum, at 230/400 V with equal power on each phase (Equal Power). It is the more powerful of the two neighbouring models: the recommended long-term load is 5.6–6.0 kW (MVD6: 4.1–4.4 kW), so the MVD8 is the one to pick when 5.5 kW is not enough. The trade-off is that the same 12.5 l tank empties sooner at full load: about 5 hours (MVD6: about 7 hours, an approximate calculation). It has an air-cooled 192FE engine, a soundproof canopy, AVR, electric start and a factory Two-Wire Switch connection that lets a hybrid inverter or an ATS cabinet start it automatically. The manufacturer states up to 12 hours of continuous running.

Technical specifications

Download the manufacturer datasheet (PDF)

How the MVD8 differs from the MVD6

Both models share the same 12.5 l fuel tank, 72 dB noise level, 230/400 V output, 15W-40 oil (1.65 l), soundproof canopy and Two-Wire Switch connection.

Choose the MVD8 if you need more power: 7.5 kW rated and a recommended long-term load of up to 6.0 kW. If your load is smaller (around 4.1–4.4 kW) or a longer run on one tank matters more, the Marsun MVD6 is the better fit: its 12.5 l lasts roughly 7 hours at full load.

Diesel generator for a home: what is the MVD8 used for?

By design the MVD8 suits backup power for homes and farms, solar systems with storage (when there is little sun and the battery is empty), building sites, workshops, allotments and outdoor events. Of the two neighbouring models the MVD8 is the more powerful one: 7.5 kW rated, with a recommended long-term load of 5.6–6.0 kW.

How much fuel does the MVD8 use and how long does a full tank last?

The manufacturer states that the MVD8 is designed for up to 12 hours of continuous running, with a 12.5 l fuel tank. It does not say what load that time applies to.

An approximate calculation at full load: 275 g/kWh × 7.5 kW ÷ 1000 = about 2.06 kg of diesel per hour. Dividing by a diesel density of 0.84 kg/l gives about 2.5 l/h, so the 12.5 l tank lasts roughly 5 hours at full rated power. This is an estimate based on the manufacturer’s consumption figure, not a measurement.

How does the MVD8 start automatically from a hybrid inverter?

The MVD8 has a factory Two-Wire Switch connection. It is a simple two-wire connection with a potential-free (dry) contact: through it a hybrid inverter or an ATS cabinet starts and stops the generator on its own, with nothing for you to do.

• A hybrid or off-grid inverter decides by itself when it needs extra energy. The generator connects to the inverter’s generator input.
• With an inverter, a separate ATS cabinet is not needed.
• At a site without solar panels, an ATS cabinet monitors the grid and starts the generator when the voltage drops out.

When the circuit closes the generator starts, and when it opens the engine shuts down safely. The manufacturer’s compatibility list includes Deye, Solis, Solplanet, GoodWe, Victron Energy and Sungrow hybrid inverters. Connection to the building’s wiring and ATS configuration must be done by a qualified electrician.

How do you connect a backup generator to a house?

A generator is connected to the building’s internal wiring through a fixed connection, and the changeover can be automated with a hybrid inverter or a separately bought ATS module. ESO (Lithuanian grid operator) states, in its recommendations for installing a backup source:

“A generator may be connected to the internal electrical network of a whole building only by installing a fixed connection and measures that ensure the voltage produced by the generator is not fed into ESO’s networks… Entrust this work only to qualified specialists.”

ESO — Recommendations for installing a backup power source

ESO also advises choosing the power according to your existing connection capacity, and when connecting single-phase loads to a three-phase generator, taking the single-phase limit into account, because the datasheet gives the combined power of all three phases.

We handle it for you. We select the equipment for your site, deliver anywhere in Lithuania, install and connect it.

Load and phases: 400 V and 230 V from one generator

From a typical three-phase generator, a single-phase socket can draw only one third of the total power. The MVD8 has an Equal Power system, with equal power on each phase, so its capacity can be used both through the 400 V power socket and through the 230 V single-phase socket.

A generator should not run at full (100%) load for long. The recommended operating range for the engine and alternator is 75 to 80% of rated power, which for the MVD8 is about 5.6 to 6.0 kW. In a system with a battery, add the power the generator will use to charge the batteries to the building’s demand.

What to know before buying

• Noise and canopy. The generator is supplied in a soundproof canopy, with a manufacturer-stated noise level of 72 dB. Choose the location with neighbours and ventilation in mind.
• Weight and size. 180 kg, 980 × 550 × 760 mm.
• Automatic changeover. There is no built-in ATS. A hybrid inverter starts the generator automatically through the Two-Wire Switch connection; at a site without an inverter you need a separately bought ATS module.
• Fuel and oil. The generator runs on diesel. It is supplied without engine oil: before the first start, add 1.65 l of 15W-40.
• What the model does not have. The MVD8 has no heated fuel block, no automatic shut-off at 10% fuel, and no online or Modbus monitoring.

Frequently asked questions

How long does the Marsun MVD8 run on a full tank?

At a full 7.5 kW load the 12.5 l tank lasts roughly 5 hours (an approximate calculation based on 275 g/kWh). The manufacturer states up to 12 hours of continuous running but does not specify the load.

How much fuel does the 7.5 kW MVD8 diesel generator use?

The manufacturer states 275 g/kWh, which at a 7.5 kW load is about 2.06 kg, or roughly 2.5 l of diesel, per hour. This is an approximate calculation.

Is the MVD8 a diesel generator with ATS?

The MVD8 has no built-in ATS; the ATS module is bought separately. With a hybrid inverter you do not need one, because the inverter starts the generator through the Two-Wire Switch connection.

Which inverters is the MVD8 compatible with?

The manufacturer’s compatibility list includes Deye, Solis, Solplanet, GoodWe, Victron Energy and Sungrow hybrid inverters. Hybrid Energy checks the connection diagram for your specific inverter and connects the system.

Can the MVD8 be connected straight to the house’s distribution board?

No, only through a fixed connection with measures that keep voltage from reaching the ESO grid, and only by qualified specialists. That is what the ESO recommendations for installing a backup source say.

Is the MVD8 diesel generator suitable for a house, a farm or a building site?

Yes. The MVD8 is meant for backup power for homes and farms, solar systems with storage, building sites, workshops, allotments and outdoor events. The recommended long-term load is about 5.6 to 6.0 kW.

How loud is the MVD8?

The manufacturer states a noise level of 72 dB, and the generator is supplied in a soundproof canopy.

Can single-phase appliances be connected to the three-phase MVD8?

Yes. The MVD8 has an Equal Power system with equal power on each phase, so the 230 V socket can be used too. Keep in mind that pumps and compressors draw 2 to 5 times more current when they start.

Does Hybrid Energy install the generator?

Yes. Hybrid Energy delivers the MVD8 anywhere in Lithuania, installs it, connects it to your site or hybrid inverter and commissions it. A consultation before you buy is free.

How does the Marsun MVD8 differ from the MVD6?

The MVD8 is rated at 7.5 kW (MVD6: 5.5 kW) with a recommended long-term load of 5.6–6.0 kW (MVD6: 4.1–4.4 kW). At full load the 12.5 l tank lasts about 5 hours (MVD6: about 7 hours); the MVD8 weighs 180 kg, the MVD6 170 kg.

Sources

• Marsun MVD8 manufacturer datasheet (PDF), checked 2026-10-26
• ESO: Recommendations for installing a backup source (in Lithuanian), checked 2026-10-26