LR250301SR Equivalent & Substitute Parts

Part Overview

The LR250301SR is a cartridge fuse holder manufactured by Littelfuse Inc., rated for 30 A at 250V with chassis mount configuration. This component is designed for single-circuit applications using Class R fuses with 0.563" diameter x 2" length cartridges. The part is currently obsolete, making identification of compatible alternatives essential for system maintenance, repair, and redesign applications.

Substiute Parts

LR250301SR

Littelfuse Inc.In Stock: 1144LR250301SR Datasheet

Current PartRFQ

LFR250301S

Littelfuse Inc.In Stock: 1251LFR250301S Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LR250301SR is based on electrical and mechanical compatibility across the following critical parameters:

• Current Rating: 30 A (exact match required)
• Voltage Rating: 250V (exact match required)
• Fuse Size: 0.563" Dia x 2" L (exact match required)
• Fuse Type: Cartridge (exact match required)
• Number of Circuits: 1 (exact match required)
• Termination Style: Screw Terminal (exact match required)
• Class R Fuse Compatibility: Required

The primary difference between the main part and its substitute lies in the mounting configuration and product status. The LR250301SR uses chassis mount, while the substitute employs DIN rail mounting. Both components accommodate identical cartridge fuses and electrical specifications, allowing functional substitution in applications where mounting method can be adapted.

Parameter Comparison

Engineering Selection Recommendations

The LFR250301S serves as the direct substitute for the obsolete LR250301SR. Both components share identical electrical ratings (30 A, 250V) and mechanical specifications (cartridge fuse size 0.563" x 2"). The LFR250301S is currently in active production status with full inventory availability.

Selection of the LFR250301S is supported by its ROHS3 compliance status, whereas the LR250301SR is RoHS non-compliant. For applications requiring regulatory compliance with modern environmental standards, the LFR250301S is the appropriate choice.

The primary design consideration is the transition from chassis mount to DIN rail mounting. This substitution is valid only in applications where the mounting infrastructure can accommodate DIN rail installation or where mechanical adaptation is feasible.

Frequently Asked Questions (FAQ)

Q: Can the LFR250301S directly replace the LR250301SR in existing installations?

A: Electrical and fuse compatibility are identical. Physical installation requires that the mounting surface support DIN rail configuration. Chassis mount applications require mechanical adaptation or redesign of the mounting structure.

Q: Are the cartridge fuses interchangeable between these two components?

A: Yes. Both the LR250301SR and LFR250301S accept Class R cartridge fuses with 0.563" diameter x 2" length specifications. Fuse selection is independent of the holder or block type.

Q: What is the significance of the RoHS compliance difference?

A: The LR250301SR is RoHS non-compliant, while the LFR250301S is ROHS3 compliant. For new designs or applications subject to environmental regulations, the LFR250301S meets current compliance requirements.

Q: Why is the LR250301SR listed as obsolete?

A: Obsolescence indicates the part is no longer manufactured. The LFR250301S represents the current production equivalent with updated compliance certifications and DIN rail mounting architecture.

Q: Are there electrical performance differences between chassis mount and DIN rail configurations?

A: No. Both configurations provide identical electrical performance at 30 A and 250V. The difference is purely mechanical in terms of installation method and physical form factor.