Littelfuse SPF004 - The SPF Solar Protection Fuse series has been specifically designed for the protection of photovoltaic (PV) systems. This family of Midget style fuses (10 x 38 mm) can safely protect PV modules and conductors from reverseovercurrent conditions. As PV systems have grown in size, so have the corresponding voltage requirements. This increase in system voltage has typically been intended to minimize power loss associated with long conductor runs. Standard circuit protection devices are not designed to completely protect photovoltaic panels. However, the SPF series is UL Listed to safely interrupt faulted circuits up to this demanding voltage level. Littelfuse offers multiple ampere ratings to match specific requirements in a variety of applications.
Littelfuse

SPF004

Alternate Item Number: 0SPF004.T

UPC: 079458169164

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Overview

The **Littelfuse SPF004 Solar Protection Fuse** is a high-performance Midget-style fuse engineered to safeguard photovoltaic (PV) systems from reverse overcurrent conditions. Designed for the unique demands of solar power applications, this 10 x 38 mm fuse provides reliable protection for PV modules and conductors, ensuring system integrity and longevity. As solar installations scale in size and voltage requirements rise to minimize power loss over long conductor runs, standard circuit protection devices often fail to meet the challenge. The **SPF series** from Littelfuse, including the SPF004, is UL Listed to safely interrupt faulted circuits at these demanding voltage levels, offering peace of mind for installers and system owners alike. **Key Features and Benefits:** - **UL Listed for High-Voltage Protection**: The SPF004 is specifically designed to handle the elevated voltage levels common in modern PV systems, ensuring compliance with safety standards and regulatory requirements. This UL certification confirms its ability to safely interrupt faulted circuits, reducing the risk of fire, equipment damage, or system downtime. - **Midget-Style Design for Versatility**: With a compact 10 x 38 mm form factor, the SPF004 is ideal for space-constrained installations, including residential rooftops, commercial solar farms, and utility-scale projects. Its standardized size ensures compatibility with a wide range of fuse holders and enclosures, simplifying integration into existing systems. - **Multiple Ampere Ratings for Customized Protection**: Littelfuse offers the SPF series in various ampere ratings to match the specific requirements of different PV applications. Whether protecting a small residential array or a large-scale solar installation, professionals can select the optimal fuse rating to ensure precise overcurrent protection without compromising system performance. - **Reverse Overcurrent Protection**: Unlike standard fuses, the SPF004 is engineered to address the unique challenges of PV systems, including reverse current flow that can occur due to shading, mismatched panels, or system faults. This specialized protection helps prevent damage to modules, conductors, and other critical components. - **Durability and Reliability**: Built to withstand the harsh environmental conditions of outdoor solar installations, the SPF004 features robust construction and high-quality materials. Its design minimizes power loss and ensures consistent performance over the lifespan of the PV system, reducing maintenance costs and maximizing energy yield. **Applications and Industries:** The Littelfuse SPF004 is a versatile solution for a broad spectrum of solar power applications. In **residential solar installations**, it protects individual PV modules or string circuits from overcurrent conditions, ensuring safe and efficient energy generation. For **commercial and industrial solar farms**, the SPF004 provides scalable protection for large arrays, where system reliability and uptime are critical. Utility-scale projects also benefit from the SPF series, as its high-voltage capabilities align with the demands of grid-tied systems and large-scale energy storage integrations. **Why Choose Littelfuse?** Littelfuse is a globally recognized leader in circuit protection, with decades of experience serving industries that demand precision and reliability. The company’s commitment to innovation and quality is evident in the SPF series, which reflects its deep understanding of the unique challenges faced by the solar power industry. Professionals in the solar sector trust Littelfuse for its adherence to stringent safety standards, extensive product testing, and responsive customer support. By choosing the SPF004, installers and system designers gain access to a trusted solution that enhances the safety, efficiency, and longevity of their PV installations. **Installation and Compliance Considerations:** When selecting and installing the SPF004, professionals should consider the specific voltage and current requirements of their PV system. The fuse should be installed in accordance with local electrical codes and manufacturer guidelines, typically within a fuse holder or enclosure rated for the system’s voltage and environmental conditions. Proper sizing and placement of the SPF004 are critical to ensuring optimal protection and compliance with regulatory standards such as the National Electrical Code (NEC) and International Electrotechnical Commission (IEC) guidelines. For engineers, contractors, and system integrators, the Littelfuse SPF004 represents a reliable and high-performance solution for safeguarding PV systems against overcurrent conditions. Its UL Listed certification, versatile design, and manufacturer-backed reliability make it an essential component in modern solar power installations, from small-scale residential setups to large-scale utility projects.
  • UL Listed for high-voltage PV system protection
  • 10 x 38 mm Midget-style fuse for compact installations
  • Multiple ampere ratings for customized overcurrent protection
  • Reverse overcurrent protection for PV-specific challenges
  • Durable construction for outdoor solar applications

Specifications

Application
1000 VDC PV
Brand Name
Littelfuse
Material
Midget-style fuse body
Series
SPF
Size
10 x 38 mm
Special Features
Solar
Standard
UL 2579 IEC 60269-6
Sub Brand
SPF Series
Type
Full Range
Voltage Rating
1000 Vdc
Package Weight (Imperial)
0.015 L
Package Weight (Metric)
7.010 g
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9F61 Size B Clips 1.6in

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POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

LCC5

POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

Frequently Asked Questions about Littelfuse

What certifications and standards do Littelfuse products comply with?

Littelfuse products are certified to multiple international standards, including UL (Underwriters Laboratories), CSA (Canadian Standards Association), CCC (China Compulsory Certification), and EAC (Eurasian Conformity). Customers can verify specific product certifications by consulting individual product datasheets on Littelfuse.com, which provide comprehensive details about standards compliance for each component.

What industries and applications are Littelfuse products used for?

Littelfuse products are critical for electrical protection and safety across multiple industrial sectors, including manufacturing, automation, power distribution, and electrical control systems. Their comprehensive product portfolio serves industries that require robust electrical protection, including motor and pump applications, solar installations, programmable logic controllers (PLCs), electrical switch panels, and critical infrastructure environments. Key product lines protect against overcurrent, voltage transients, ground faults, and temperature-related electrical risks, ensuring equipment safety and operational reliability.

What technical support does Littelfuse offer?

Littelfuse offers comprehensive technical support through multiple channels. Their Technical Hotline (800-TEC-FUSE) provides direct access to engineers who can help identify issues and recommend solutions. Additionally, Littelfuse offers extensive online Technical Resources at Littelfuse.com, including datasheets, product manuals, whitepapers, application guides, and online design tools. Their experienced product and application engineers also provide step-by-step support from design to installation.

What are the main product lines offered by Littelfuse?

Littelfuse offers comprehensive industrial protection and control product lines, including fuses, fuse holders, protection relays, temperature sensors, and electrical safety components. Their key product categories span surge protective devices, custom OEM products, electrical switch panels, medium voltage fuses, ground-fault protection relays, motor and pump protection devices, and temperature sensors. These products are designed to minimize electrical safety hazards, limit equipment damage, improve productivity, and safeguard personnel from electrical faults.

What are the key features of Littelfuse products?

Littelfuse products feature exceptional circuit protection technologies with key characteristics including UL/IEC safety standard compliance, low internal resistance, and advanced protective capabilities across multiple product lines. Their components provide critical protection for industrial systems, offering features like overcurrent protection, voltage transient suppression, and resettable protection devices with ultra-low resistance and compact designs. Key product lines include fuses, metal oxide varistors (MOVs), TVS diodes, PolySwitch devices, and specialized electronic protection components that enhance system reliability and safety.

What environmental ratings do Littelfuse products have?

Littelfuse products feature comprehensive environmental ratings, including NEMA Type 1, 2, 3, 3R, 4/4X, 12, and 13 certifications, as well as IP65 protection. These ratings ensure superior protection in diverse industrial environments, with an operating temperature range of -40°F to +131°F (-40°C to +55°C). Many products also include UV-stabilized materials and neoprene gaskets for enhanced durability in outdoor and challenging conditions.

What accessories are available for Littelfuse products?

Littelfuse offers several key accessories across their product lines, including fuse holders, voltage monitoring modules, and terminal connectors. Specific accessories include the LPSM003ZXID (indicating) and LPSM003Z (non-indicating) POWR-SAFE Dead Front fuse holders for Class CC and Midget-Style fuses, the VRM6048 voltage monitor accessory module, and female quick connect terminals (P1015 series) in various wire gauge sizes. These accessories are designed to enhance protection, monitoring, and connectivity for Littelfuse electrical components.

What is Littelfuse's warranty policy?

Littelfuse provides comprehensive warranty details on their official website at www.littelfuse.com/warranty. Customers should visit this page to review the specific warranty terms and conditions for their specific product lines. For direct warranty support or questions, customers can contact Littelfuse Technical Support at 1-800-TEC-FUSE or email [email protected].

What communication protocols do Littelfuse products support?

Littelfuse supports a comprehensive range of industrial communication protocols, including PROFIBUS, PROFINET, EtherNet/IP, DeviceNet, Modbus RTU, and CANopen. Our products provide flexible connectivity solutions across multiple industrial automation platforms, enabling seamless integration with various control systems and network architectures.

How are Littelfuse products typically installed?

Littelfuse products are typically installed using specialized mounting hardware like fuse holders, blocks, and panels designed for specific industrial applications. The POWR-SAFE Dead Front holders, for example, provide optimum protection for Class CC and Midget-Style fuses, supporting installations up to 600 VAC/DC. Installation often involves using precision terminals with strain relief, such as 0.25 in. female quick connect terminals, to ensure secure and safe electrical connections in industrial control systems.