Reliable Switching for Clean Energy

Solar photovoltaic systems and energy storage require robust switching solutions that can handle high DC currents, provide safety isolation, and maintain reliable operation over decades of service life.

HONGFA relays provide the performance, safety, and longevity needed for solar inverters, battery systems, and grid-tie applications in the rapidly growing renewable energy sector.

Solar PV System Architecture

Solar Energy Market Growth

20%

Annual Growth
Global solar market CAGR through 2030

1,000GW

Installed Capacity
Global solar PV target by 2030

$1.8T

Investment
Required for renewable transition

50%

Cost Reduction
Solar LCOE decrease since 2020

Solar & Energy Storage Applications

☀️

String Inverters

DC switching and isolation relays for residential and commercial string inverters.

  • 1000VDC switching capability
  • Arc suppression technology
  • UL 1741 compliant
  • 20-year service life

Recommended: HONGFA HVDC series

🔋

Energy Storage Systems

Battery management and protection relays for grid-scale and residential ESS.

  • High current DC switching
  • Emergency disconnect function
  • Fire safety integration
  • Remote monitoring capability

Recommended: HF18FF industrial series

Grid-Tie Systems

Utility interconnect and protection relays for grid-connected solar installations.

  • IEEE 1547 compliance
  • Anti-islanding protection
  • Utility grade reliability
  • Remote disconnect capability

Recommended: HFE18 latching series

🏭

Central Inverters

High-power switching solutions for utility-scale solar power plants and farms.

  • MW-scale power handling
  • Parallel operation capability
  • Maintenance disconnect
  • Weather-resistant design

Recommended: Custom high-power series

🏠

Residential Solar

Compact, cost-effective relays for rooftop solar and home energy systems.

  • Compact form factor
  • Easy installation
  • Code compliance
  • Long-term reliability

Recommended: HF115F power series

📊

Monitoring & Control

Signal and control relays for performance monitoring and system optimization.

  • Low-level signal switching
  • Data acquisition support
  • Communication interface
  • Environmental monitoring

Recommended: HFD3 signal series

Solar System Relay Challenges

DC Arc Suppression

Unlike AC systems, DC arcs don't naturally extinguish at zero-crossing points, making DC switching more challenging. Solar relays must incorporate advanced arc suppression technologies.

High Voltage Operation

Modern solar systems operate at up to 1000VDC, requiring specialized relay designs with enhanced dielectric strength and creepage distances.

Environmental Exposure

Outdoor installations subject relays to UV radiation, temperature cycling, humidity, and contamination. Relay selection must account for 20-25 year service life requirements.

Safety & Code Compliance

Solar installations must meet stringent electrical codes including NEC Article 690, UL 1741, and IEEE 1547 standards for grid interconnection.

Rapid Shutdown Requirements

NEC 690.12 requires rapid shutdown capability for rooftop installations, demanding relays that can quickly isolate DC circuits during emergencies.

Maintenance Access

Service disconnect switches must provide visible isolation for maintenance work, often requiring manual operation capability alongside remote control.

HONGFA Solar Relay Solutions

High-Voltage DC Switching

Key Features:

  • 1000VDC switching capability
  • Advanced arc chamber design
  • Silver alloy contacts optimized for DC
  • High dielectric strength (>5kV)
  • Rapid switching response (<10ms)
  • Parallel operation capability

Performance Benefits:

  • Reliable arc extinction
  • Minimal contact erosion
  • Low contact resistance
  • Extended electrical life
  • Reduced maintenance requirements
  • Enhanced safety operation

Environmental Protection

  • UV Resistance: Housing materials tested to ASTM G154 standards
  • Temperature Cycling: -40°C to +85°C operation with cycling endurance
  • Moisture Protection: IP65/IP67 sealing for outdoor installations
  • Chemical Resistance: Compatible with cleaning agents and environmental contaminants

Solar Application Relay Specifications

Application Voltage Rating Current Rating Key Requirements
String Inverter DC Input 1000VDC 15-30A Arc suppression, UL 1741
Battery ESS Disconnect 600VDC 100-300A Emergency disconnect, fire safety
AC Grid Disconnect 480VAC 50-100A IEEE 1547, anti-islanding
Combiner Box 1000VDC 10-20A String isolation, monitoring
Rapid Shutdown 80VDC 5-15A Fast response, NEC 690.12

Customer Success Story

Major Solar Inverter Manufacturer

"We've been using HONGFA's high-voltage DC relays in our string inverters for over 5 years. Their consistent performance and reliability have been crucial to our product success. The technical support from LiTong helped us optimize our designs for both performance and cost, enabling us to maintain our market leadership position."

Results achieved:

  • 99.7% field reliability over 5-year deployment
  • 15% reduction in warranty claims vs. previous relay supplier
  • Successful UL 1741 certification for all product lines
  • On-time delivery performance >98% for high-volume orders

— Chief Technology Officer, Leading Solar Inverter Company

Solar Development Support

Code Compliance

Expert guidance on NEC, UL, and IEEE standards for solar installations and grid-tie systems.

Access Resources →

Arc Testing

DC arc suppression testing and validation services for high-voltage solar applications.

Request Testing →

Custom Solutions

Specialized relay configurations for unique solar and energy storage requirements.

Discuss Custom Needs →

Power the Future with Reliable Solar Solutions

Our solar relay experts can help you design safer, more reliable renewable energy systems.

Start Your Solar Project