MJS 5 Equivalent & Substitute Parts

Part Overview

The MJS 5 is a 5A 250VAC glass cartridge fuse in 2AG form factor (5mm x 15mm axial) manufactured by Bel Fuse Inc. This through-hole mounted fuse is designed for slow-blow response characteristics and is rated for both AC and DC applications. The main part (MJS 5) carries an obsolete product status, making identification of active equivalent parts essential for ongoing system support and component procurement.

Substiute Parts

MJS 5

Bel Fuse Inc.In Stock: 1019MJS 5 Datasheet

Current PartRFQ

MJS 5-R

Bel Fuse Inc.In Stock: 903MJS 5-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The MJS 5-R qualifies as a direct substitute for the MJS 5 based on the following critical parameters:

• Current Rating: 5 A (identical)
• Voltage Rating (AC): 250 V (identical)
• Fuse Type: Cartridge, Glass (identical)
• Package / Case: 2AG, 5mm x 15mm (Axial) (identical)
• Response Time: Slow Blow (identical)
• Mounting Type: Through Hole (identical)
• Breaking Capacity @ Rated Voltage: 200A (identical)
• Operating Temperature Range: -55°C ~ 125°C (identical)

The MJS 5-R maintains full electrical and mechanical compatibility with the obsolete MJS 5, with the primary distinction being product status (Active vs. Obsolete) and packaging format (Bulk vs. standard).

Parameter Comparison

Engineering Selection Recommendations

The MJS 5-R is the direct active equivalent for the obsolete MJS 5. Selection of the MJS 5-R is appropriate for all applications currently using the MJS 5, as electrical and mechanical parameters are identical. The MJS 5-R offers improved regulatory compliance with ROHS3 certification and expanded approval agency recognition (cULus certification). The marginal reduction in DC cold resistance (0.019 Ohms vs. 0.022 Ohms) remains within acceptable tolerance for fuse cartridge applications and does not affect functional performance in standard circuit protection scenarios.

Frequently Asked Questions (FAQ)

Q: Can the MJS 5-R be used as a direct replacement for the MJS 5?

A: Yes. The MJS 5-R is electrically and mechanically identical to the MJS 5 across all critical parameters: current rating, voltage rating, fuse type, package form factor, response time, and operating temperature range. Direct substitution is valid.

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

A: The primary differences are product status (MJS 5 is obsolete; MJS 5-R is active), packaging format (standard vs. bulk), RoHS compliance (non-compliant vs. ROHS3 compliant), and minor variations in DC cold resistance and approval certifications. Electrical and mechanical performance are equivalent.

Q: Are there any compatibility concerns with the 2AG package form factor?

A: No. Both parts use the identical 2AG, 5mm x 15mm (Axial) package specification. Physical dimensions and through-hole mounting characteristics are identical, ensuring direct PCB and socket compatibility.

Q: Does the lower DC cold resistance of the MJS 5-R affect circuit performance?

A: No. The reduction from 0.022 Ohms to 0.019 Ohms is negligible for fuse cartridge applications and does not impact circuit protection characteristics or thermal performance in standard operating conditions.

Q: Which certifications does the MJS 5-R carry?

A: The MJS 5-R carries CE, CSA, cULus, and PSE approvals. This represents expanded certification coverage compared to the MJS 5 (CE, CSA, PSE, UL), with cULus providing combined Canadian and US UL recognition.