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Littelfuse LFT600303S - 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.

Littelfuse LFT600303S The new Littelfuse Class T fuse blocks offer many advantages over previous generations…

Alternate Item Number: LFT600303S

UPC: 079458938623


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BrochureTechnical Drawing3D CAD Model (IGES)Specification 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 LFT600303S Class T fuse block delivers a significant space-saving advantage over previous generations, reducing panel footprint by up to 45% while maintaining full electrical performance. Designed for industrial electrical protection, this fuse block supports voltage ratings of 300 V and 600 V with ampere ratings from 0 to 600 A, making it suitable for high-current applications in control panels, motor circuits, and power distribution systems. Engineered for reliability, the LFT600303S features a thermoplastic base for durability, tin-plated copper alloy fuse clips for low contact resistance, and aluminum box lugs for secure conductor termination. Zinc-plated steel fuse studs and screws ensure corrosion resistance, while the UL 94 V-0 flammability rating provides enhanced safety in demanding environments. The fuse block offers a withstand rating of 200 kA RMS SYM and leakage current of less than 0.6 mA at 600 V, ensuring stable operation under fault conditions. Installation is simplified with snap-to-release DIN rail mounting for 30–60 A fuses, allowing one-hand release for faster setup. Reinforced fuse clips are standard, and 60 A box lugs include both hex and slot set screw options for flexible wiring. Covers are available for most amperage ratings to enhance safety and prevent accidental contact. Recommended fuses include Littelfuse JLLN for 300 V and JLLS for 600 V applications. Ideal for industrial machinery, commercial buildings, and renewable energy systems, the LFT600303S Class T fuse block combines compact design with robust construction, ensuring long-term reliability in high-current protection applications.
  • Space-saving design reduces panel footprint by up to 45%
  • Supports 300 V and 600 V with 0–600 A ratings
  • Thermoplastic base with tin-plated copper alloy fuse clips
  • Snap-to-release DIN rail mounting for 30–60 A fuses
  • Withstand rating of 200 kA RMS SYM and <0.6 mA leakage at 600 V

Specifications

Brand Name
Littelfuse
Special Features
Universal mounting holes
Standard
UL Listed and CSA Certified RoHS
Sub Brand
LFT 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
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SH20-P3T53J4

2000W 5V 150A 24V 10A 2-12V 1P
3PH6P18MM is a compact-sized POWR Busbar system that provides safe distribution of electrical power to multiple dead front fuse holders and measures 104 mm in length, which can be cut down to an optimal size. See datasheet for more detailed specifications.

3PH6P18MM

3PH6P18MM is a compact-sized POWR Busbar system that provides safe distribution of electrical power to multiple dead front fuse holders and measures 104 mm in length, which can be cut down to an optimal size. See datasheet for more detailed specifications.
The Littelfuse 600 V Class J blocks offer generous space savings and enhanced value over previous generations, such as indication, snap-to-release DIN-rail mounting and universal mounting holes.

LFJ60030-1SID

The Littelfuse 600 V Class J blocks offer generous space savings and enhanced value over previous generations, such as indication, snap-to-release DIN-rail mounting and universal mounting holes.
The Littelfuse 600 V Class J blocks offer generous space savings and enhanced value over previous generations, such as indication, snap-to-release DIN-rail mounting and universal mounting holes.

LFJ60060-2CID

The Littelfuse 600 V Class J blocks offer generous space savings and enhanced value over previous generations, such as indication, snap-to-release DIN-rail mounting and universal mounting holes.
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.

LFR25100-3CID

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.

Frequently Asked Questions

What are the voltage ratings for the Littelfuse LFT600303S fuse block?

The Littelfuse LFT600303S Class T fuse block supports both 300 V and 600 V voltage ratings.

What is the ampere rating range for this fuse block?

The Littelfuse LFT600303S fuse block is designed for ampere ratings from 0 to 600 A.

What materials are used in the construction of the LFT600303S fuse block?

The fuse block features a thermoplastic base, tin-plated copper alloy fuse clips, aluminum box lugs, and zinc-plated steel fuse studs and screws.

Is the Littelfuse LFT600303S fuse block UL listed and CSA certified?

Yes, the Littelfuse LFT600303S fuse block is UL Listed under File E14721 and CSA Certified under File LR7316.

What is the withstand rating of the LFT600303S fuse block?

The Littelfuse LFT600303S fuse block has a withstand rating of 200 kA RMS SYM.

What are the recommended fuses for the LFT600303S fuse block?

For 300 V applications, Littelfuse JLLN fuses are recommended. For 600 V applications, JLLS fuses are recommended.

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.