3JS 5 Equivalent & Substitute Parts Reference

Part Overview

The 3JS 5 is a 5A 350VAC/140VDC glass cartridge fuse in 2AG form factor (5mm x 15mm axial) manufactured by Bel Fuse Inc. This component is classified as obsolete, necessitating identification of active equivalent parts for ongoing system support and procurement. The slow-blow response characteristic and through-hole mounting design make this fuse suitable for general-purpose circuit protection applications requiring moderate current ratings and dual voltage operation.

Substiute Parts

3JS 5

Bel Fuse Inc.In Stock: 8143JS 5 Datasheet

Current PartRFQ

3JS 5-R

Bel Fuse Inc.In Stock: 14223JS 5-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3JS 5 is determined by strict equivalence across the following critical parameters:

• Current Rating: 5 A (exact match required)
• Voltage Rating - AC: 350 V (exact match required)
• Voltage Rating - DC: 140 V (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Package / Case: 2AG, 5mm x 15mm (Axial) (exact match required)
• Response Time: Slow Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Breaking Capacity @ Rated Voltage: 100A AC, 150A DC (exact match required)
• Melting I²t: 135 (exact match required)

The 3JS 5-R variant from Bel Fuse Inc. meets all substitution criteria as a direct equivalent. This part maintains identical electrical and mechanical specifications while offering improved compliance status and availability.

Parameter Comparison

Engineering Selection Recommendations

The 3JS 5-R is the direct equivalent substitute for the obsolete 3JS 5. Both parts maintain identical electrical performance, mechanical form factor, and regulatory certifications (CE, CSA, cURus, PSE). The 3JS 5-R offers the advantage of active product status and ROHS3 compliance, making it the preferred selection for new designs and ongoing procurement. The DC cold resistance differential (0.022 Ohms vs. 0.018 Ohms) falls within acceptable tolerance for this component class and does not affect functional equivalence.

Frequently Asked Questions (FAQ)

Q: Can the 3JS 5-R be used as a direct replacement for the 3JS 5 in existing applications?

A: Yes. The 3JS 5-R is electrically and mechanically equivalent to the 3JS 5 across all critical parameters: current rating, voltage ratings, fuse type, package form factor, response time, and breaking capacity. Direct substitution is supported without circuit modification.

Q: What is the difference between the 3JS 5 and 3JS 5-R?

A: The primary differences are product status and compliance. The 3JS 5 is obsolete and RoHS non-compliant, while the 3JS 5-R is an active product with ROHS3 compliance. Electrical and mechanical specifications are identical.

Q: Are there packaging differences between these parts?

A: The 3JS 5 is supplied in standard packaging, while the 3JS 5-R is supplied in bulk packaging. Both maintain the same 2AG, 5mm x 15mm (Axial) form factor and are compatible with identical PCB footprints and through-hole mounting positions.

Q: What certifications apply to both parts?

A: Both the 3JS 5 and 3JS 5-R carry CE, CSA, cURus, and PSE approvals, ensuring compliance with international safety standards for circuit protection devices.

Q: Is the DC cold resistance difference significant?

A: No. The DC cold resistance values (0.022 Ohms for 3JS 5 and 0.018 Ohms for 3JS 5-R) represent normal manufacturing variation within acceptable tolerance for this component class and do not affect functional performance or circuit behavior.