FLNR004 - 4 Amp Fuse

FLNR004 - 4 Amp Fuse

When your circuit has normal startup or inrush current, you don't necessarily want a fuse opening the moment that brief surge occurs. The Littelfuse FLNR004 is a 4A Class RK5 time-delay fuse built for that kind of application. Its dual-element, Slo-Blo design allows the fuse to handle temporary current increases while still providing overcurrent protection when conditions call for it.

Key Features and Benefits

• 4A continuous current rating for circuits designed around a 4-amp fuse.
• Class RK5 construction for compatible industrial and commercial electrical systems.
• Time-delay performance helps accommodate temporary current surges that can occur during normal equipment operation.
• Dual-element design combines time-delay characteristics with overcurrent protection.
• Handles voltages up to 250 VAC and 125 VDC.
• Interrupting rating up to 300 kA AC and 20 kA DC, depending on the application.
• Industrial cartridge format designed for installation in compatible fuse blocks, clips, and holders.
• Straightforward non-indicating design with no visual blown-fuse indicator.
  

Technical Specifications

• Catalog Number: FLNR004
  
• Series: FLNR
  
• Product Type: Industrial cartridge fuse
  
• Fuse Class: Class RK5
  
• Current Rating: 4A continuous
  
• Maximum AC Voltage: 250VAC
  
• Maximum DC Voltage: 125VDC
  
• Interrupting Rating: Up to 300 kA AC; 20 kA DC
  
• Opening Type: Slo-Blo / Time Lag / Time Delay
  
• Fuse Style: Dual Element
  
• Construction: Industrial Cartridge
  
• Indicating: No
  
• Mounting Method: Fuse Block / Clip / Holder
  
• Compatible Holder Series: LFR25030 Series
  

Material Compliance and Certifications

The FLNR004 is a Class RK5 fuse, with manufacturer specifications identifying its electrical characteristics and industrial cartridge construction. Its published specifications include a 4A continuous current rating, maximum ratings of 250VAC and 125VDC, dual-element time-delay operation, and the stated AC and DC interrupting ratings.

Where It Works Best

The FLNR004 makes the most sense in industrial and commercial electrical applications where brief inrush currents are a normal part of operation. That's where its time-delay characteristic matters.

It's also a natural fit for maintenance and replacement work when the existing equipment specifically calls for a 4A, 250V Class RK5 time-delay cartridge fuse. Before replacing any fuse, check the required amperage, voltage, fuse class, interrupting rating, opening characteristics, and physical fit.