FLSR600 - 600 Amp Fuse

FLSR600 - 600 Amp Fuse

When you're replacing a 600-amp fuse, getting the catalog number right is only part of the job. The FLSR600 is a 600A Class RK5 dual-element time-delay fuse built for electrical systems requiring knife-blade construction and ratings up to 600V AC or 300V DC. Its Slo-Blo/Time Lag characteristic is particularly useful in properly specified circuits where brief startup or inrush current is normal—you get the time-delay behavior the equipment calls for without treating every temporary current surge as a fault.

Key Features and Benefits

• 600A continuous rating – Made for circuits specifically engineered around 600-amp fuse protection.
• Class RK5 – Gives you the fuse classification needed when the equipment specification calls for RK5.
• Time-delay operation – The Slo-Blo/Time Lag characteristic accommodates appropriate short-duration startup and inrush current within the fuse's specified operating limits.
• Dual-element construction – Combines dual-element operation with the required time-delay response.
• Knife-blade style – Straightforward physical configuration for compatible fuse blocks, clips, and holders.
• Non-indicating design – An important detail when matching an existing FLSR600 or equipment specification.
  

Technical Specifications

• Catalog Number: FLSR600
  
• Series: FLSR
  
• Fuse Type: Dual-Element Time-Delay Fuse
  
• Fuse Class: Class RK5
  
• Continuous Current Rating: 600A
  
• Maximum AC Voltage: 600V AC
  
• Maximum DC Voltage: 300V DC
  
• Opening: Slo-Blo / Time Lag (T) / Time Delay
  
• Size / Construction: Knife-Blade
  
• Family Style: Dual Element Fuse
  
• Indicating: No
  
• DC Interrupting Rating: 20 kA at 300V DC
  
• Manufacturer-Listed AC Interrupt Amperage: 200,000A and 300,000A at 600V AC*
  
• Mounting Method: Fuse Block / Clip / Holder
  
• PG Holder: LFR60600 Series
  

Material Compliance and Certifications

Here's an area where it pays not to guess. The supplied manufacturer information identifies the FLSR600 as a Class RK5 fuse but does not provide catalog-specific UL, CSA, RoHS, or other material-compliance details.

Where It Works Best

The FLSR600 is a practical match for properly engineered electrical equipment calling for a 600A Class RK5 time-delay fuse. Its Slo-Blo characteristic becomes especially relevant in applications where temporary startup or inrush current is expected, and the system has been designed around the fuse's time-current characteristics.

It also makes sense as a like-for-like replacement when the existing specification calls for an FLSR600, knife-blade construction, and a non-indicating configuration. For maintenance personnel, that makes identification easier—but don't rely on the 600A marking alone. Confirm the fuse class, AC or DC voltage requirements, interrupting capacity, time-delay characteristic, and holder compatibility as part of the replacement check.