STF 520: POWER THAT NEVER QUITS

Pure sine wave off-grid solar inverter built for India. Two models: 3.5KW (24V) and 5.5KW (48V). Scalable up to 30KW by connecting 6 units in parallel. IoT enabled for smartphone monitoring. Perfect for homes, farms, and businesses.

ADVANCED TECHNICAL BRILLIANCE

Built-in 100A MPPT controller extracts 30% more solar energy. Ultra-wide PV input (120-500VDC) simplifies installation. 4-in-1 operating modes with battery/grid/solar flexibility. Pure sine wave output protects sensitive electronics. Advanced battery equalization extends lifespan.

VERSATILE APPLICATIONS & WARRANTY

Ideal for rural homes, agricultural equipment, off-grid resorts, commercial installations up to 30KW, and telecom backup. Intelligent power priority control ensures uninterrupted supply. Backed by a 2-year manufacturer warranty for peace of mind.

STF 520: Power That Never Quits

Uninterruptible Power. Unlimited Freedom. Built for India.

In a nation where energy reliability is the foundation of progress, your home, farm, or business demands a power solution that performs flawlessly. Siri Technofabs proudly introduces the STF 520 Off-Grid Solar Inverter—a pure sine wave powerhouse engineered to deliver continuous, stable, and independent electricity, even in the most remote or grid-challenged areas of India.

Choose Your Powerhouse: STF 520 Models

The STF 520 series offers two high-capacity models to perfectly match your power requirements, with the flexibility to scale up to 30KW for large-scale projects:

STF 520 - 3.5KW
3.5 KW
Battery Voltage 24V
Best For Homes & Offices

Ideal for smaller homes, offices, and robust backup needs.

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STF 520 - 5.5KW
5.5 KW
Battery Voltage 48V
Best For Home & Commercial Use

Perfect for larger installations, commercial use, and heavy-duty.

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🌐 Smart Monitoring Anywhere

Both models are IoT enabled, allowing you to monitor and manage your system's performance, generation, and status right from your smartphone, no matter where you are.

Core Advantages & Technical Brilliance

The STF 520 is packed with cutting-edge features that simplify your installation and maximize your return on investment:

Feature Your Practical Benefit
Massive Scalability Power Up to 30KW: Connect and operate up to 6 units in parallel to meet huge power demands, making it perfect for industrial and large commercial installations.
Pure Sine Wave Output Safety for Electronics: Delivers exceptionally clean and stable power, ensuring your sensitive appliances (ACs, PCs, medical equipment) run reliably and last longer.
Built-in 100A MPPT Controller Maximized Solar Gain: Intelligently tracks sunlight to extract up to 30% more energy from your PV panels compared to systems with traditional controllers.
Ultra-Wide PV Input (120VDC–500VDC) Simplified & Cost-Effective Installation: The broad voltage range allows connecting more panels in series, dramatically reducing wiring complexity and overall system costs.
Unrivaled Flexibility 4-in-1 Operating Modes: Can seamlessly operate With or Without a Battery, and manages connections to the Grid and Solar simultaneously, providing true energy versatility.
Intelligent Power Priority Complete Control: Use the user-friendly LCD to easily dictate the source priority (Solar, Battery, or Grid), guaranteeing uninterrupted power even in highly unstable grid conditions.
Advanced Battery Equalization Extended Battery Life: Automatically balances the charge across all battery cells, preventing premature wear and tear and significantly prolonging the lifespan of your battery bank.
Universal Load Support Works with Anything: Designed to work efficiently with virtually any type of load up to its mentioned capacity (3.5KW or 5.5KW).
Warranty Assurance Peace of Mind: Backed by a Two-Year Warranty, confirming our commitment to quality and reliable performance.

Ideal Applications Across India

The robust and flexible design of the STF 520 makes it the perfect solution for a variety of critical power needs across the country:

Rural & Remote Homes

Ensures essential 24/7 electricity access where the grid is unreliable or non-existent.

Agricultural Use

Reliably powers essential farm equipment, pump motors, and high-wattage lighting during critical operations.

Off-Grid Cabins & Resorts

Provides a dependable, high-quality power source for remote tourism and leisure facilities.

Commercial & Industrial

The ability to scale up to 30KW makes it ideal for large workshops, small factories, and commercial establishments.

Telecom & Monitoring

Delivers critical, stable backup power for communication infrastructure and off-grid monitoring sites.

Warranty & Assurance

We stand by the quality of the STF 520. Every unit purchased from Siri Technofabs comes with comprehensive warranty coverage:

Two-Year Warranty

Standard manufacturer's warranty against any manufacturing defects, ensuring your long-term investment is protected.

Quality Assurance

Rigorous testing and quality control processes ensure every unit meets the highest standards of performance and reliability.

Technical Support

Dedicated technical support team available to assist with installation, troubleshooting, and maintenance throughout the warranty period.

Ready to Transform Your Power Management?

Download the complete technical details and data sheet to explore the STF 520's full potential, or contact us for a customized quote.