3JQ 4 Glass Cartridge Fuse Equivalent & Substitute Parts

Part Overview

The 3JQ 4 is a fast-blow glass cartridge fuse rated for 4 A at 350 V AC and 140 V DC, designed for through-hole mounting in 2AG package format (5mm x 15mm axial). The main part (3JQ 4) carries an obsolete product status, making identification of active equivalent parts essential for ongoing system support and component procurement. The substitute part 3JQ 4-R maintains identical electrical and mechanical specifications while offering active product status and improved compliance characteristics.

Substiute Parts

3JQ 4

Bel Fuse Inc.In Stock: 9523JQ 4 Datasheet

Current PartRFQ

3JQ 4-R

Bel Fuse Inc.In Stock: 12163JQ 4-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3JQ 4 fuse is determined by strict equivalence across the following critical parameters:

• Current Rating: 4 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)
• Response Time: Fast Blow (exact match required)
• Package / Case: 2AG, 5mm x 15mm (Axial) (exact match required)
• Mounting Type: Through Hole (exact match required)
• Breaking Capacity @ Rated Voltage: 100 A AC, 150 A DC (exact match required)
• Melting I²t: 12 (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)
• Approval Agencies: CE, CSA, cURus, PSE (exact match required)

The substitute part 3JQ 4-R satisfies all substitution criteria and is classified as a direct equivalent.

Parameter Comparison

Engineering Selection Recommendations

The 3JQ 4-R is the direct equivalent substitute for the obsolete 3JQ 4 fuse. Both parts maintain identical electrical ratings, mechanical dimensions, and thermal characteristics. The 3JQ 4-R offers the advantage of active product status, ensuring continued availability and supply chain reliability. Additionally, the 3JQ 4-R achieves ROHS3 compliance, whereas the original 3JQ 4 is RoHS non-compliant. Both parts carry equivalent international approvals (CE, CSA, cURus, PSE), confirming suitability for regulated applications. The marginal difference in DC cold resistance (0.02 Ohms versus 0.019 Ohms) is within acceptable engineering tolerance and does not affect functional performance in circuit applications.

Frequently Asked Questions (FAQ)

Q: Can the 3JQ 4-R be used as a direct replacement for the 3JQ 4?

A: Yes. The 3JQ 4-R is a direct equivalent substitute. All electrical ratings (4 A, 350 V AC, 140 V DC), mechanical specifications (2AG package, 5mm x 15mm), response characteristics (fast blow), and thermal operating range (-55°C ~ 125°C) are identical. Both parts carry the same international approvals.

Q: What is the difference between the 3JQ 4 and 3JQ 4-R?

A: The primary differences are product status and compliance. The 3JQ 4 is obsolete and RoHS non-compliant, while the 3JQ 4-R is active and ROHS3 compliant. The DC cold resistance differs marginally (0.02 Ohms versus 0.019 Ohms), which is within acceptable tolerance and does not impact circuit performance.

Q: Are there packaging differences between these parts?

A: The 3JQ 4 is supplied in standard packaging, while the 3JQ 4-R is supplied in bulk packaging. Both maintain identical component specifications and are compatible with the same through-hole mounting footprints.

Q: Does the 3JQ 4-R meet the same regulatory approvals as the 3JQ 4?

A: Yes. Both parts carry CE, CSA, cURus, and PSE approvals, confirming compliance with international safety and performance standards.

Q: What is the breaking capacity of these fuses?

A: Both the 3JQ 4 and 3JQ 4-R have a breaking capacity of 100 A AC and 150 A DC at rated voltage, ensuring reliable fault protection in circuit applications.