Littelfuse FLSR004 - FLSR004 is a Class RK5 fuse with an ampere rating of 4 and cartridge-style construction.
Littelfuse

FLSR004

Alternate Item Number: FLSR004.T

UPC: 079458170535


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Minimum Qty: 10

Multiplier: 10

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Overview

The **Littelfuse FLSR004** is a high-performance **Class RK5 cartridge-style fuse** engineered for robust industrial circuit protection. Designed with a **4A current rating**, this fuse delivers precise overcurrent interruption while safeguarding sensitive electronic equipment, motors, and control systems from damaging fault conditions. As part of Littelfuse’s esteemed **Class RK5 series**, the FLSR004 combines durability, reliability, and compliance with stringent industrial standards, making it a trusted choice for engineers and maintenance professionals across diverse sectors. **Key Features and Benefits:** - **Precision Interruption:** The **4A rating** ensures accurate response to overcurrent events, preventing nuisance tripping while protecting critical components from thermal and electrical damage. - **Class RK5 Compliance:** Meets **RK5 performance criteria**, offering superior interrupting capacity and coordination with downstream protective devices, ideal for complex industrial distribution systems. - **Cartridge-Style Construction:** The **cartridge design** provides a secure fit in compatible fuse blocks, reducing installation errors and ensuring consistent electrical contact for long-term reliability. - **Industrial-Grade Durability:** Built to withstand harsh environments, the FLSR004 resists vibration, temperature fluctuations, and electrical stress, ensuring dependable operation in demanding applications. - **Wide Application Compatibility:** Suitable for use in **motor control centers, panelboards, switchgear, and industrial machinery**, where reliable fault protection is critical to operational safety and uptime. **Typical Applications:** The **Littelfuse FLSR004** is widely deployed in industries such as **manufacturing, oil and gas, mining, and renewable energy**, where circuit protection is paramount. Common use cases include: - **Motor starters and controllers**, where it protects windings and wiring from overloads. - **Power distribution panels**, ensuring selective coordination to isolate faults without disrupting entire systems. - **Control circuits and PLCs**, safeguarding sensitive electronics from transient surges and short circuits. - **Lighting and HVAC systems**, providing reliable protection in commercial and industrial facilities. **Why Choose Littelfuse?** With over a century of innovation in circuit protection, **Littelfuse** is a global leader in designing solutions that enhance safety and reliability in industrial applications. The **FLSR004** exemplifies the company’s commitment to quality, backed by rigorous testing and adherence to international standards such as **UL and IEC**. Professionals trust Littelfuse for its **consistent performance, extensive product range, and responsive technical support**, ensuring seamless integration into existing systems. **Installation and Maintenance Considerations:** Proper selection and installation of the **FLSR004** are critical to maximizing its protective capabilities. Engineers should verify compatibility with the fuse block or holder, ensuring the correct voltage and interrupting rating for the application. Regular inspections for signs of wear, corrosion, or overheating are recommended to maintain optimal performance. For applications requiring **high inrush currents** (e.g., motors or transformers), consult Littelfuse’s application guides to select the appropriate fuse size and type. **Conclusion:** For industrial professionals seeking a **reliable, high-quality fuse** that delivers **precision protection and long-term durability**, the **Littelfuse FLSR004 Class RK5 4A cartridge fuse** is an exceptional choice. Its robust construction, compliance with industry standards, and versatile applications make it a cornerstone of modern circuit protection strategies. Trust Littelfuse to provide the **performance and peace of mind** your operations demand.
  • 4A current rating for precise overcurrent protection
  • Class RK5 compliance for superior interrupting capacity
  • Cartridge-style construction for secure installation
  • Industrial-grade durability for harsh environments
  • Wide compatibility with motors, panels, and control systems

Specifications

Application
General Purpose
Brand Name
Littelfuse
Current Rating
4 A
Series
Class RK5
Size
Cartridge-style
Special Features
Time-Delay
Standard
Standard 248-12 UL Listed/CSA
Sub Brand
POWR-GARD FLSR Series
Type
Class RK5
Package Weight (Imperial)
0.152 L
Package Weight (Metric)
69.200 g
Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount

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Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount
Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20

C331156

Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20
Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8

1SCM8

Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8
Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20

E1062696

Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20
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.
9F61 Size B Clips 1.6in

9F61BWW460

9F61 Size B Clips 1.6in

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.