Launch of the Marstek Smart Box: the “brain” that coordinates your home energy storage at scale

Meet the Marstek Smart Box, an energy management device that controls and optimises the power flows between your solar panels, your battery, and your home loads.

It enables your batteries to switch into backup mode automatically so that, in the event of a blackout, you can keep the essentials running.

What is the Marstek Smart Box and what is it for?

The Marstek Smart Box lets you connect up to 3 Venus E 3.0 batteries in parallel, tripling continuous output to 7,500 W and storage to 15 kWh in each phase of your electrical panel.

Based on the Smart Meter measurements of your main line’s power inflow and outflow, it automatically decides when to charge or discharge, when to use solar, and when to draw from the grid—so your home gets the most out of every kWh. It ensures you store all excess solar energy, to not feed any into the grid but use it at home when the sun doesn’t shine.
It includes automatic backup during outages and zero-export control (to avoid injecting surplus energy into the grid).

The Marstek Smart Box is available in two models:

• Single-phase (DB63S)
  
• Three-phase (DB63T)

How does backup work during blackouts?

The backup function (also called backup/emergency mode) allows the system to keep powering your home if there’s a grid outage.

The Smart Box automatically detects the interruption and switches the power source from the grid to the Marstek Venus E 3.0 batteries, so your appliances keep running without interruption.

Transfer is fast (typically under a second), avoiding shutdowns of sensitive equipment.

During a blackout, the Smart Box isolates your solar system from the public grid, preventing back-feeding. This is a technical and legal requirement designed to protect grid workers.

Power and autonomy

Output power depends on how many batteries you connect. For example, one Marstek Venus E 3.0 can deliver up to 2,500 W of continuous output—enough for essentials like a fridge, router, lights, computer or TV.

You can connect up to three Venus E 3.0 units to reach 7,500 W in each phase. Storage capacity, and hence your autonomy, varies with total capacity (5 kWh, 10 kWh, 15 kWh) and the consumption of the devices you power.

How to configure batteries with the Marstek Smart Box in each phase:

*Note: real-world autonomy depends on each home’s consumption.

*The table refers to each phase of the electrical circuit. With the three-phase Smart Box, you can size up to 3 Venus E 3.0 batteries per phase (9 total), reaching up to 22,500 W output and 46.08 kWh of storage capacity.

Zero-export and efficiency

With zero-export enabled, the system avoids injecting surplus into the grid and prioritises self-consumption, helping you maximise the use of your solar production. This is especially useful if you must meet export limits (or if you simply want to make the most of your PV output).

Technical data of the Marstek Smart Box

• AC output: 50/60 Hz, max 40 A
  
  • Single-phase model (DB63S): 220/230 V
    
  • Three-phase model (DB63T): 380/400 V
    
• Dimensions (L × W × H):
  
  • DB63S (single-phase): 360 × 134 × 480 mm
    
  • DB63T (three-phase): 380 × 134 × 500 mm
    
• Transfer time: ~1 s
  
• Operating modes: On-grid / Off-grid (with bypass for maintenance)
  
• Operating temperature: −5 °C to +70 °C; humidity <95% RH
  
• Protection rating: IP20; natural cooling
  

Why choose the Marstek Smart Box?

Stay powered in blackouts. Keep your essentials running thanks to backup mode.

Save more with your solar. Let the Smart Box manage charge/discharge and enable zero-export to increase self-consumption.

Scale as you need. Start with one battery and expand up to three Marstek Venus E 3.0 units as your needs grow.

Discover the new Marstek Smart Box and write to us if you have any questions.