Littelfuse LFR604003C - The new Littelfuse Class H and R blocks offer many advantages over previous generations that are noted in the features and benefits section. Class H and Class R fuse blocks are dimensionally the same, but Class R blocks incorporate a rejection feature, which only allows Class R fuses to be inserted.
Littelfuse

LFR604003C

Alternate Item Number: LFR604003C

UPC: 079458181418

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Overview

The Littelfuse Class H and R fuse blocks (SKU: LFR604003C) represent a significant advancement in industrial fuse protection, combining dimensional consistency with critical safety features. Designed for compatibility and reliability, these fuse blocks are engineered to meet the rigorous demands of modern industrial environments, where equipment protection and operational safety are paramount. Class H and Class R fuse blocks share identical dimensions, simplifying installation and replacement in existing systems while offering distinct advantages tailored to specific applications. The key differentiator lies in the Class R blocks, which incorporate a rejection feature—a mechanical safeguard that ensures only Class R fuses can be inserted. This prevents the accidental installation of incompatible fuses, a common cause of equipment damage, downtime, and safety hazards in industrial settings. Industrial professionals rely on Littelfuse for its legacy of innovation and reliability in circuit protection. With decades of expertise, Littelfuse has established itself as a trusted partner for engineers, panel builders, and maintenance teams who demand solutions that deliver consistent performance under the most challenging conditions. The Class H and R fuse blocks are no exception, offering robust construction, precise engineering, and adherence to industry standards that ensure long-term durability and dependable operation. Whether deployed in control panels, power distribution systems, or machinery, these fuse blocks provide the protection needed to safeguard critical assets and maintain operational continuity. The versatility of the Littelfuse Class H and R fuse blocks makes them ideal for a wide range of applications across multiple industries. In manufacturing facilities, they are commonly used in motor control centers, machinery protection circuits, and branch distribution panels where reliable overcurrent protection is essential. Electrical contractors and system integrators favor these fuse blocks for their ease of installation and compatibility with existing infrastructure, reducing project timelines and minimizing the risk of errors during deployment. The rejection feature in Class R blocks is particularly valuable in applications where regulatory compliance or safety protocols mandate the use of specific fuse types, such as in food processing, pharmaceuticals, or hazardous locations where equipment integrity is non-negotiable. Selecting the right fuse block involves considering several factors, including the type of fuses required, the environmental conditions of the installation site, and the specific performance characteristics needed for the application. Littelfuse’s Class H and R fuse blocks are designed to accommodate a broad spectrum of fuse ratings, ensuring compatibility with a wide range of industrial equipment. The blocks are constructed from high-quality materials that resist corrosion, vibration, and thermal stress, making them suitable for both indoor and outdoor environments. Additionally, their modular design allows for easy expansion or reconfiguration as system requirements evolve, providing a scalable solution for growing operations. Installation of the Littelfuse Class H and R fuse blocks is straightforward, thanks to their standardized dimensions and user-friendly design. Professionals can mount these blocks on DIN rails or directly onto panels, depending on the system configuration. The rejection feature in Class R blocks is seamlessly integrated, requiring no additional tools or adjustments to activate. This ensures that even in high-pressure maintenance scenarios, the risk of human error is minimized. Furthermore, Littelfuse provides comprehensive documentation and support resources, including wiring diagrams, technical specifications, and application notes, to assist engineers and technicians in achieving optimal performance from their installations. For industries where reliability and safety are non-negotiable, the Littelfuse Class H and R fuse blocks offer a compelling solution. Their combination of dimensional consistency, rejection technology, and robust construction addresses the most common pain points in industrial fuse protection, from accidental misapplication to premature failure. By choosing Littelfuse, professionals gain access to a product line backed by a manufacturer with a proven track record of innovation and customer support. Whether upgrading existing systems or designing new installations, the Class H and R fuse blocks provide the peace of mind that comes from knowing critical equipment is protected by a trusted name in circuit protection.
  • Dimensional consistency between Class H and Class R blocks for easy replacement
  • Class R blocks feature a rejection mechanism to prevent incorrect fuse installation
  • Robust construction for reliable performance in demanding industrial environments
  • Compatible with a wide range of fuse ratings for versatile applications
  • Trusted Littelfuse quality with decades of expertise in circuit protection

Specifications

Brand Name
Littelfuse
Special Features
Universal mounting holes
Standard
UL Listed and CSA Certified RoHS
Sub Brand
LFR Series
Type
Fuse Block
Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount

GPM-SRR90

Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount
BB18 is a three-phase busbar terminal power feed lug, which is intended for use with LPSM/LPSC series fuse holders. See datasheet for more detailed specifications.

BB18

BB18 is a three-phase busbar terminal power feed lug, which is intended for use with LPSM/LPSC series fuse holders. See datasheet for more detailed specifications.
D4/8.SFT2.I.ADO

1SNA399777R1200

D4/8.SFT2.I.ADO
2000W 5V 150A 24V 10A 2-12V 1P

SH20-P3T53J4

2000W 5V 150A 24V 10A 2-12V 1P

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.