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Littelfuse LRU-2621R - For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

Littelfuse LRU-2621R For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

Alternate Item Number: LRU2621R

UPC: 079458010695


Documents & Media
BrochureTechnical BulletinSpecification Sheet

Contact for Pricing

Call +1 (262) 252-1600 (toll-free 877-268-3700) or email [email protected] for pricing and availability.

Overview

The Littelfuse LRU-2621R fuse holder is a UL-listed industrial-grade component designed for secure mounting of Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK, and KLNR/KLSR series fuses. This fuse holder ensures reliable electrical contact and protection in power distribution panels, industrial machinery, and automation systems. Compatible with multiple Littelfuse fuse series, it simplifies maintenance by allowing quick fuse replacement without system shutdown. The LRU-2621R features a durable thermoplastic housing rated for high-temperature environments and meets UL 94 V-0 flammability standards. Its compact design supports DIN rail mounting for efficient panel integration. The holder includes a spring-loaded terminal design to maintain consistent pressure and reduce contact resistance, enhancing long-term reliability. The LRU-2621R is engineered for harsh environments, offering resistance to vibration and mechanical stress while ensuring compliance with IEC 60127-6 standards for fuse holders. Ideal for applications requiring fast fuse access and minimal downtime, this holder enhances system safety by maintaining consistent electrical continuity. Trust Littelfuse’s US-manufactured LRU-2621R for dependable performance in harsh industrial conditions.
  • UL-listed industrial-grade fuse holder for Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK & KLNR/KLSR series fuses
  • Durable thermoplastic housing rated for high-temperature environments, UL 94 V-0 flammability compliant
  • DIN rail mounting for efficient panel integration and space-saving design
  • Enables quick fuse replacement without system shutdown, reducing maintenance downtime
  • US-manufactured by Littelfuse for reliable performance in harsh industrial conditions

Specifications

Application
Industrial
Brand Name
Littelfuse
Material
Thermoplastic
Mounting Type
DIN Rail
Series
LRU
Series
FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK, KLNR/KLSR
Special Features
Simple Installation
Standard
UL Listed CSA Certified
Sub Brand
LRUR Series
Type
Fuse Reducer
Cover DFC Series 600VAC 200A Class J

DFC-12

Cover DFC Series 600VAC 200A Class J
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LRU-263

Littelfuse® fuse reducers allow smaller size fuses to be installed into existing fuse clips to prevent overfusing.
ECRAN ENTRE PHASES T00

63010015

ECRAN ENTRE PHASES T00
Littelfuse® fuse reducers allow smaller size fuses to be installed into existing fuse clips to prevent overfusing.

LRU-2661

Littelfuse® fuse reducers allow smaller size fuses to be installed into existing fuse clips to prevent overfusing.
For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

LRU-2641R

For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.
For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

LRU-213R

For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.
For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

LRU-2662R

For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.
For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

LRU-2642R

For use with Littelfuse FLNR_ID/FLSR_ID, IDSR, LLNRK/LLSRK and KLNR/KLSR series fuses.

Frequently Asked Questions

What types of fuses does Littelfuse offer for industrial applications?

Littelfuse offers UL Class fuses, high-speed fuses, medium voltage fuses, 10 x 38 mm fuses, and solar fuses for industrial applications.

What are Littelfuse high-speed fuses used for?

High-speed fuses protect critical power semiconductor devices against short circuits in power conversion applications like inverters and variable-speed drives.

What applications are medium voltage fuses designed for?

Medium voltage fuses protect transformers, potential transformers, feeders, and motor circuits, with designs available for various current, voltage, and mounting configurations.

What are the voltage and amperage ranges for 10 x 38 mm fuses?

10 x 38 mm fuses range from 125 to 1000 volts and 1/10 to 30 amperes.

What is the maximum DC voltage for Littelfuse solar fuses?

Littelfuse offers solar fuses and holders up to 1500 Vdc for photovoltaic applications.

What protection do feeder protection relays offer?

Feeder protection relays protect circuits from overcurrent, ground faults, phase loss, overload, and other detrimental conditions.

What is the Industrial Shock-Block® GFCI designed for?

The Industrial Shock-Block® GFCI is designed for people protection in industrial facilities and meets UL Standard 943C Class C and Class D.

What kind of protection do Littelfuse voltage monitors provide?

Voltage monitors provide protection against both supply line and load side faults when the motor is running.

What functions can Littelfuse timers and flashers control?

Timers and flashers can delay starting and stopping loads, and control cycling and sequencing of motors, pumps, compressors, heaters, and lighting.

How do arc-flash protection relays enhance safety?

Arc-flash relays detect developing arc-flash incidents and send a trip signal to interrupt power before significant damage occurs.

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.