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LITTELFUSE Fuse: Class L, KLLU Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC - Time-Delay Bolt-On Fuses
LITTELFUSETime-Delay Bolt-On Fuses

LITTELFUSE Fuse: Class L, KLLU Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC

The LITTELFUSE KLLU Series Class L Time-Delay Bolt-On Fuse (MPN KLLU4000X) is a 4 kA, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in…

SKU 3G-OTH-27769

Brand
LITTELFUSE
Item
Fuse: Class L, KLLU Series, Bolt-On Body, Time-Delay, 4 kA, 600 V AC
Category
Time-Delay Bolt-On Fuses
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

LITTELFUSE
Manufacturer Part Number
KLLU4000X
Series
KLLU
Type
KLLU Series, Bolt-On Body, Time-Delay, 4 kA
AC
600 V
DC
300 V

Technical Documents

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LITTELFUSE Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The LITTELFUSE KLLU Series Class L Time-Delay Bolt-On Fuse (MPN KLLU4000X) is a 4 kA, 600 V AC, 300 V DC industrial fuse with a bolt-on body. This time-delay fuse is designed for overcurrent protection in high-current applications.

Frequently Asked Questions

What is the LITTELFUSE KLLU4000X fuse used for?

The LITTELFUSE KLLU4000X is a Class L time-delay bolt-on fuse rated 4 kA, 600 V AC, 300 V DC. It provides overcurrent protection in high-current industrial applications such as switchboards, panelboards, and motor control centers where high interrupting capacity is required.

What are the specifications of the LITTELFUSE KLLU4000X?

The LITTELFUSE KLLU4000X is a KLLU Series Class L fuse with a bolt-on body, time-delay characteristic, 4 kA rating, 600 V AC, and 300 V DC. The manufacturer part number is KLLU4000X. It is designed for high-current overcurrent protection in industrial circuits.

Where to buy the LITTELFUSE KLLU4000X worldwide?

3G Electric supplies the LITTELFUSE KLLU4000X fuse to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this Class L time-delay bolt-on fuse.

How to select the correct LITTELFUSE KLLU4000X fuse for an application?

To select the LITTELFUSE KLLU4000X, verify your circuit voltage does not exceed 600 V AC or 300 V DC and that the continuous current is within the 4 kA rating. Ensure the bolt-on mounting matches your fuse holder. Consult a qualified engineer for coordination with upstream protection devices.

Used in

Common applications for LITTELFUSE
Power electronics protection — Littelfuse PSR Series semiconductor fuses for IGBT and diode protection in variable frequency drives.
Solar photovoltaic systems — Littelfuse SPF Series fast-acting fuses for string overcurrent protection in PV arrays.
Automotive electrical systems — Littelfuse MIDI® 498 Series bolt-on fuses for battery and alternator protection in vehicles.
Industrial control panels — Littelfuse KLKD Series midget fuses for branch circuit protection in control transformers and relays.
Motor control centers — Littelfuse BLF Series fast-acting fuses for short-circuit protection of motor starters and contactors.

LITTELFUSE Products

3G Electric supplies LITTELFUSE time-delay bolt-on fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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