SB 4.0

The SMA Sunny Boy SB 4.0 (SB4.0-1AV-41) is the 4 kW single-phase inverter from the Sunny Boy 3.0–6.0 series, designed by SMA Solar Technology for medium-sized residential photovoltaic systems. With a maximum PV field power of 7,500 Wp, it is suitable for homes with medium-high energy consumption and medium-sized roofs, offering the right balance between power and cost in a unit weighing just 17.5 kg.

2 Independent MPPTs — Optimal Management of Complex Roofs

The SB 4.0 features 2 independent MPP trackers (input A and input B), each with 2 connectable strings. This architecture allows you to manage different roof sections with varying orientations or inclinations separately, maximizing overall production. The MPP range goes from 140 V to 500 V, with a maximum DC voltage of 600 V and a maximum output current of 22 A in AC.

SMA OptiTrac Global Peak and TS4-R — Shading Under Control

Shading management takes place on two levels:

• SMA OptiTrac Global Peak (integrated) — an algorithm that identifies the global maximum power point on the I-V curve even in the presence of multiple local maxima due to partial shading
• Integrated TS4-R Communication — native compatibility with SMA TS4-R module optimizers, which can be installed selectively only where needed without replacing the inverter

SMA Smart Connected — Proactive Monitoring and Replacement

By registering the system on Sunny Portal, SMA Smart Connected is automatically activated: SMA monitors the inverter 24/7 and, in case of an anomaly, proactively notifies the installer and owner via email. If replacement is necessary, SMA ships a replacement inverter within 1–3 working days from diagnosis — with guaranteed reimbursement in case of delay. Available in Italy at no additional cost.

Installation and Communication

Commissioning is done via an integrated web interface accessible by smartphone, tablet, or notebook, with no dedicated software required. Communication interfaces include:

• WLAN — direct connection to the home router for online monitoring
• Ethernet (SMA Speedwire) — for wired networks and connection to SMA Home Manager / Data Manager
• RS485 — for integration with BMS or building automation systems
• Protocols: Modbus SMA/SunSpec, Webconnect, SMA Data, TS4-R

Free online monitoring via Sunny Portal and Sunny Places.

Expandability — Storage and Energy Management

The SB 4.0 integrates natively with the SMA residential ecosystem:

• SMA Sunny Home Manager 2.0 — intelligent energy management with AI to maximize self-consumption
• Compatible SMA Storage Systems — expandable with batteries at any time after installation
• SMA EV Charger — integrated electric vehicle charging within the home energy system
• Dynamic Active Power Limitation — reduces grid withdrawals during periods of excess production

Full Technical Specifications

• Model: SB4.0-1AV-41
• Nominal AC power: 4,000 W / 4,000 VA
• Max PV generator power: 7,500 Wp
• No. of MPPTs: 2 independent (2 strings per MPPT)
• Max DC voltage: 600 V
• MPP range: 140–500 V
• Max DC current per input: 15 A / 15 A
• Nominal AC voltage: 230 V (range 180–280 V)
• Max AC current: 22 A
• Frequency: 50 Hz
• Max / European efficiency: 97.0% / 96.5%
• Topology: transformerless
• Cooling: natural convection
• Noise level: 25 dB(A)
• Nighttime self-consumption: 1.0 W
• Degree of protection: IP65
• Operating temperature: −25°C to +60°C
• Communication: WLAN / Ethernet / RS485
• DC connection: SUNCLIX
• Standard warranty: 5 years (extendable to 10 or 15 years)
• Certifications: CEI 0-21, CE, VDE-AR-N 4105, G83/2-1, EN 50438 and others
• Dimensions (W×H×D): 435 × 470 × 176 mm
• Weight: 17.5 kg