LLNRK070 - 70Amp Fuse

LLNRK070 - 70Amp Fuse

When a motor starts, or a transformer powers up, a brief current surge is perfectly normal. The last thing you want is a blown fuse bringing everything to a halt when nothing is actually wrong. That's where the Littelfuse LLNRK070 70 Amp Class RK1 time-delay fuse comes in. Part of the Littelfuse POWR-PRO™ series, this dual-element fuse tolerates temporary startup currents while providing dependable protection against sustained overloads and short circuits.

Meanwhile, low-resistance construction helps limit power losses during everyday operation. The fuse also features a thermally reversible, spring-loaded overload element that provides time-delay performance without unnecessary openings during normal inrush conditions, helping maintain an older electrical installation. The Littelfuse LLNRK070 time-delay fuse can also be installed in compatible existing Class H fuse blocks, improving short-circuit protection in systems that previously used lower-interrupting-rating Class H fuses. From motor control equipment to service entrance and feeder circuits, the LLNRK070 delivers the kind of protection that helps keep electrical systems working as intended.

Key Features and Benefits

• 70 Amp Continuous Current Rating
• 250V AC / 125V DC Voltage Ratings
• Class RK1 Current-Limiting Protection
• High Short-Circuit Interrupting Capacity
• Dual-Element Time-Delay Design
• Reduced Nuisance Fuse Openings
• Thermally Reversible Overload Element
• Low-Resistance Construction
• Compatible Class H Fuse Block Upgrades
• Non-Indicating Design

Technical Specifications

• Manufacturer: Littelfuse
  
• Catalog Number: LLNRK070
  
• Product Series: LLNRK
  
• Product Family: POWR-PRO™
  
• Product Type: Current-Limiting Time-Delay Fuse
  
• Fuse Class: Class RK1
  
• Continuous Current Rating: 70 Amps
  
• Maximum AC Voltage: 250V AC
  
• Maximum DC Voltage: 125V DC
  
• AC Interrupting Ratings: 200,000A and 300,000A at 250V AC, as listed by the manufacturer
  
• DC Interrupting Rating: 20,000A at 125V DC
  
• Opening Characteristic: Slo-Blo / Time Lag / Time Delay
  
• Element Configuration: Dual-Element
  
• Overload Element: Thermally Reversible, Spring-Loaded
  
• Fuse Indication: Non-Indicating
  
• Mounting Method: Fuse Block / Clip / Holder
  
• Compatible Holder Series: LFR25100
  
• Fuse Block Compatibility: Suitable for Class RK1 and compatible existing Class H fuse blocks
  

Material Compliance and Certifications

The Littelfuse LLNRK070 is part of the POWR-PRO Class RK1 fuse family, engineered for overload and short-circuit protection in electrical distribution and equipment circuits.

• Material Compliance: Verify current RoHS and REACH declarations with Littelfuse
• Safety Certifications: Confirm applicable UL, CSA, and other approvals using current manufacturer documentation

For installations with specific regulatory or material requirements, review the manufacturer's latest compliance declarations and certification records before selecting the fuse.

Where It Works Best

• Industrial Motors
• Transformers
• Service Entrance Equipment
• Main and Feeder Circuits
• General-Purpose Branch Circuits
• Solenoids
• Fluorescent Lighting Systems
• High-Inrush Electrical Equipment
• Electrical Distribution Systems
• Class H Fuse System Upgrades