Littelfuse LFR25100-1CID - 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

LFR25100-1CID

Alternate Item Number: LFR251001CID

UPC: 079458181661

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Overview

The Littelfuse Class H and R fuse blocks, specifically the LFR25100-1CID model, represent a significant advancement in overcurrent protection technology for industrial environments. Engineered by Littelfuse, a globally recognized leader in circuit protection, these fuse blocks offer enhanced safety, reliability, and operational efficiency compared to previous generations. A key distinguishing feature is their dimensional identity between Class H and Class R configurations, simplifying integration into existing systems. However, the Class R variant incorporates a crucial rejection feature. This intelligent design ensures that only compatible Class R fuses can be inserted into the block, effectively preventing the inadvertent installation of incorrect fuse types. This rejection mechanism is paramount in critical applications where misapplication of fuses can lead to equipment damage, system downtime, and potential safety hazards. These fuse blocks are indispensable components in a wide array of industrial applications, including but not limited to: * **Industrial Control Panels:** Providing essential protection for sensitive control circuitry and automation components. * **Power Distribution Systems:** Safeguarding main power feeds and branch circuits in manufacturing facilities, data centers, and commercial buildings. * **Motor Control Centers (MCCs):** Protecting individual motor circuits from overloads and short circuits. * **Renewable Energy Systems:** Ensuring the reliable operation of inverters and other critical components in solar and wind power installations. * **Heavy Machinery:** Offering robust protection for the electrical systems of large industrial equipment. The Littelfuse LFR25100-1CID is designed to meet stringent industry standards, providing consistent performance and long-term durability even under demanding operating conditions. The commitment to quality and innovation by Littelfuse ensures that these fuse blocks deliver superior protection, minimizing the risk of electrical faults and contributing to the overall safety and productivity of industrial operations. Professionals selecting fuse blocks for their critical infrastructure will find the Littelfuse Class H and R series to be a reliable and secure choice, offering peace of mind through advanced safety features and proven manufacturing excellence. The rejection feature in the Class R blocks, in particular, addresses a common point of failure in electrical installations, making it a vital consideration for any application requiring the highest levels of safety and operational integrity. Investing in Littelfuse fuse blocks means investing in dependable circuit protection that supports the continuous and safe operation of your industrial assets.
  • Enhanced safety with Class R fuse rejection mechanism
  • Dimensionally identical Class H and Class R configurations
  • Prevents incorrect fuse insertion, reducing risk of damage and hazards
  • Ideal for industrial control panels, power distribution, and motor control
  • Manufactured by Littelfuse, a trusted leader in circuit protection

Specifications

Brand Name
Littelfuse
Connection Type
Screw Terminal
Series
Class H and R
Series
Class H/R
Special Features
Universal mounting holes
Standard
UL Listed and CSA Certified RoHS
Sub Brand
LFR Series
Type
Fuse Block
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LD4551-3

POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.
PWR DIST BLK (REPLACED BY LFD55863Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.

LD5586-3

PWR DIST BLK (REPLACED BY LFD55863Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.
3AG MTG 5 POLE NEMA STYLE 3/16. A low profile fuse block featuring individual barriers which reinforce the fuse clips while providing greater protection against clip damage and electrical shock. The unique design permits self-alignment of clips to fuse cap. This, plus a one-piece clip/terminal assures low contact resistance. Higher current ratings have been attained using spring brass clips. With the exception of the two-pole unit, multiple pole units may be broken apart to obtain desired number of poles.

354605-GY

3AG MTG 5 POLE NEMA STYLE 3/16. A low profile fuse block featuring individual barriers which reinforce the fuse clips while providing greater protection against clip damage and electrical shock. The unique design permits self-alignment of clips to fuse cap. This, plus a one-piece clip/terminal assures low contact resistance. Higher current ratings have been attained using spring brass clips. With the exception of the two-pole unit, multiple pole units may be broken apart to obtain desired number of poles.
OMNI-BLOK MTG 12 POLE. A low profile fuse block featuring individual barriers which reinforce the fuse clips while providing greater protection against clip damage and electrical shock. The unique design permits self-alignment of clips to fuse cap. This, plus a one-piece clip/terminal assures low contact resistance. Higher current ratings have been attained using spring brass clips. With the exception of the two-pole unit, multiple pole units may be broken apart to obtain desired number of poles.

354912-GY

OMNI-BLOK MTG 12 POLE. A low profile fuse block featuring individual barriers which reinforce the fuse clips while providing greater protection against clip damage and electrical shock. The unique design permits self-alignment of clips to fuse cap. This, plus a one-piece clip/terminal assures low contact resistance. Higher current ratings have been attained using spring brass clips. With the exception of the two-pole unit, multiple pole units may be broken apart to obtain desired number of poles.
SPLICER BLOCK WIRE TERMINAL

WCL007

SPLICER BLOCK WIRE TERMINAL
PWR DIST BLK (REPLACED BY LFD25703Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.

LD2570-3

PWR DIST BLK (REPLACED BY LFD25703Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.
POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.

LD3552-2

POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.
POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.

LS3126-1

POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.
The new Littelfuse Class T fuse blocks offer many advantages over previous generations that are noted in the features and benefits section. Of particular value is the space savings these new blocks provide.

LFT602001CS

The new Littelfuse Class T fuse blocks offer many advantages over previous generations that are noted in the features and benefits section. Of particular value is the space savings these new blocks provide.
POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.

LFD5552-3

POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.
POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.

LD2570-2DIN

POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover.
PWR DIST BLK (REPLACED BY LFD14003Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.

LD1400-3

PWR DIST BLK (REPLACED BY LFD14003Z). POWR-BLOKS power distribution blocks offer a safe, convenient way of splicing cables, providing a fixed junction tap-off point or splitting primary power into secondary circuits. LX2XXX-DIN series offers integral DIN-Rail mount and an optional hinged safety cover. Applications: Typical applications include heating, air conditioning and refrigeration systems, elevator systems, material handling equipment, control panels, motor controls, switchgear, and anywhere power needs to be distributed to more than one load.

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.