KLLU4000 - 4000Amp Fuse

KLLU4000 - 4000Amp Fuse

When your electrical system calls for a 4000A Class L time-delay fuse, the catalog number is only the first step in verifying compatibility. The KLLU4000 is a high-amperage, current-limiting fuse with bolt-in construction, a maximum rating of 600VAC and 300VDC, and a time-delay opening characteristic. The manufacturer also identifies the KLLU Series as UL Listed and states that it meets or exceeds UL requirements for Class L fuses. For a replacement or new application, confirm the full set of electrical and physical requirements—including amperage, Class L configuration, voltage, interrupting capacity, time-delay characteristics, and bolt-in mounting—rather than relying on the 4000A rating alone.

Key Features and Benefits

• 4000A continuous current rating for equipment designed around a 4000-amp Class L fuse.
• Class L configuration provides a defined fuse class for accurate application and replacement matching.
• The time-delay opening characteristic is designed for circuits where you must account for temporary starting current.
• The manufacturer specifies a minimum 10-second time delay at 500% of the fuse rating, helping prevent unnecessary operation during heavy starting currents from large motors and other inductive loads.
• The current-limiting design helps reduce short-circuit damage to systems and equipment.
• Handles AC applications up to 600VAC.
• Also rated for DC applications up to 300VDC, when all other system requirements are satisfied.
• Bolt-in mounting makes the physical connection style another straightforward specification to verify before installation.
• Non-indicating design matches applications that specifically call for this configuration.

Technical Specifications

• Catalog Number: KLLU4000
  
• Manufacturer Description: FUS 600V T/D CLASS L 4000A
  
• Series: KLLU
  
• Product Type: Time-Delay Current-Limiting Fuse
  
• Continuous Current Rating: 4000A
  
• Maximum AC Voltage: 600VAC
  
• Maximum DC Voltage: 300VDC
  
• AC Interrupting Rating: 200,000A at 600VAC
  
• DC Interrupting Rating: 20,000A at 300VDC
  
• Opening Characteristic: Slo-Blo / Time Lag (T) / Time Delay
  
• Specified Time Delay: Minimum 10 seconds at 500% of rated current
  
• Fuse Class: Class L
  
• Family Style: Current Limiting
  
• Construction / Size: Bolt-In
  
• Indicating: No
  
• Mounting Method: Bolt-In
  

Material Compliance and Certifications

The manufacturer identifies the KLLU Series as UL Listed, time-delay Class L fuses and states that the series meets or exceeds UL requirements for Class L fuses. The supplied information for KLLU4000 further identifies it as a 4000A Class L fuse with current-limiting characteristics, time-delay operation, and bolt-in mounting.

Where It Works Best

The KLLU4000 4000A Class L fuse suits electrical equipment designed for a 4000A, time-delay, current-limiting Class L fuse with bolt-in mounting. The manufacturer specifically identifies motor branch-circuit protection as an application for the KLLU Series. Its minimum 10-second time delay at 500% of rating is intended to accommodate the heavy starting currents associated with large motors and other inductive loads. At the same time, its current-limiting characteristic is designed to reduce short-circuit damage to equipment and systems.