Littelfuse FLNR400ID Class RK5 Fuse – 400A – 250V Time-Delay Indicating Fuse

The Littelfuse FLNR400ID is a 400 Amp Class RK5 dual-element time-delay fuse designed for industrial and commercial electrical protection applications. Part of the FLNR_ID series, this fuse incorporates a built-in blown-fuse indicator that provides quick visual status identification, reducing troubleshooting and maintenance time. Its dual-element construction delivers reliable overload and short-circuit protection while accommodating temporary motor starting and transformer inrush currents.

Electrical Rating

• Current Rating: 400 Amps
• Maximum AC Voltage: 250 VAC
• Maximum DC Voltage: 125 VDC
• Interrupting Rating:
  • 300 kA AC
  • 20 kA DC

Key Specifications

• Manufacturer: Littelfuse
• Catalog Number: FLNR400ID
• Series: FLNR_ID
• Fuse Class: RK5
• Construction Type: Knife-Blade
• Fuse Type: Dual Element Time-Delay
• Indicating: Yes

Protection Characteristics

• Time-delay (slow-blow) operation
• Dual-element fuse design
• Provides overload and short-circuit protection
• Allows temporary motor and transformer inrush currents without nuisance opening
• High interrupting capacity for industrial power distribution systems

Construction Features

• Knife-blade terminal construction
• Visual blown-fuse indication feature
• Industrial-duty design for demanding applications
• Durable construction for long-term reliability

Mounting & Compatibility

• Mounting Method: Fuse Block / Clip / Holder
• Compatible with standard Class RK5 fuse holders and fuse blocks
• Suitable for switchboards, panelboards, and industrial control equipment

Applications

• Motor branch circuit protection
• Transformer protection
• Industrial machinery and equipment
• Commercial electrical distribution systems
• Feeder and branch circuit protection

Product Data

• Manufacturer: Littelfuse
• Catalog Number: FLNR400ID
• Product Type: Indicating Time-Delay Fuse
• Series: FLNR_ID
• Fuse Class: RK5

Returns are easy

You may return items within 30 days of delivery for a refund.

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