KLDR004.T Equivalent & Substitute Parts

Part Overview

The KLDR004.T is a 4A cartridge fuse rated for 600 VAC / 300 VDC operation, manufactured by Littelfuse Inc. under the POWR-GARD® KLDR series. This component is classified as a slow-blow fuse designed for transformer protection applications and features a 5AG (10mm x 38mm midget) form factor. The part is currently listed as obsolete, making identification of active equivalent substitutes essential for procurement and system continuity.

Substiute Parts

KLDR004.T

Littelfuse Inc.In Stock: 756KLDR004.T Datasheet

Current PartRFQ

KLDR004.TXP

LittelfuseIn Stock: 1400KLDR004.TXP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the KLDR004.T is determined by strict equivalence across the following parameters:

• Current Rating: 4A (exact match required)
• Voltage Rating: 600 VAC / 300 VDC (exact match required)
• Response Time: Slow Blow (exact match required)
• Fuse Class: CC (exact match required)
• Physical Form Factor: 5AG cartridge, 10mm x 38mm midget (exact match required)
• Approval Certifications: CE, CSA, UL (must be present)
• RoHS Compliance: ROHS3 Compliant (must be maintained)

The KLDR004.TXP is a direct substitute manufactured by Littelfuse under the same POWR-GARD® KLDR series. It maintains identical electrical specifications, mechanical dimensions, and regulatory compliance while offering active product status and improved availability.

Parameter Comparison

Engineering Selection Recommendations

The KLDR004.TXP is the direct equivalent for KLDR004.T applications. Selection is based on the following factors:

• Product Status: KLDR004.TXP maintains active status with current manufacturing support, whereas KLDR004.T is obsolete and subject to supply discontinuation.
• Regulatory Compliance: Both parts maintain identical CE, CSA, and UL certifications, ensuring compliance with applicable standards.
• RoHS Compliance: KLDR004.TXP maintains ROHS3 compliance, meeting environmental and regulatory requirements.
• Electrical and Mechanical Equivalence: All critical parameters—current rating, voltage ratings, response time, fuse class, and physical dimensions—are identical, ensuring direct interchangeability in existing circuit designs and mechanical assemblies.

Frequently Asked Questions (FAQ)

Q: Can KLDR004.TXP be used as a direct replacement for KLDR004.T?

A: Yes. KLDR004.TXP is electrically and mechanically equivalent to KLDR004.T. Both parts share identical current ratings (4A), voltage ratings (600 VAC / 300 VDC), response time (slow blow), fuse class (CC), and physical dimensions (5AG, 10mm x 38mm). Both require the same holder assembly and are suitable for transformer protection applications.

Q: What is the primary advantage of selecting KLDR004.TXP over KLDR004.T?

A: KLDR004.TXP is an active product with current manufacturing support and improved inventory availability. KLDR004.T is obsolete and subject to supply constraints. For new designs and ongoing procurement, KLDR004.TXP ensures supply continuity and long-term availability.

Q: Are there any differences in packaging between these parts?

A: KLDR004.T is supplied with standard packaging, while KLDR004.TXP is supplied in box packaging. Both parts maintain identical electrical specifications and physical form factors. Packaging differences do not affect functional performance or interchangeability.

Q: Do both parts meet the same regulatory certifications?

A: Yes. Both KLDR004.T and KLDR004.TXP carry CE, CSA, and UL certifications and are ROHS3 compliant. They meet identical regulatory and environmental standards.

Q: What holder assembly is required for these fuses?

A: Both KLDR004.T and KLDR004.TXP require a compatible fuse holder designed for 5AG cartridge fuses (10mm x 38mm midget form factor). The holder must be rated for 600 VAC / 300 VDC operation.