3AB 1 Ceramic Fuse Equivalent & Substitute Parts

Part Overview

The 3AB 1 is a 1 A, 250 V AC/DC ceramic cartridge fuse manufactured by Bel Fuse Inc. designed for fast-blow protection in electrical circuits requiring compact form factor and reliable interruption. The main part (3AB 1) is classified as obsolete, necessitating identification of active equivalent components to maintain supply chain continuity and ensure design compatibility in applications where this fuse type is specified.

Substiute Parts

3AB 1

Bel Fuse Inc.In Stock: 10053AB 1 Datasheet

Current PartRFQ

3AB 1-R

Bel Fuse Inc.In Stock: 17003AB 1-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3AB 1 is based on strict equivalence across the following critical parameters:

• Current Rating: 1 A (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Fuse Type: Cartridge, Ceramic (exact match required)
• Response Time: Fast Blow (exact match required)
• Physical Package: 3AB, 3AG, 1/4" x 1-1/4" (exact match required for holder compatibility)
• Breaking Capacity: 35 A @ rated voltage (exact match required)
• Operating Temperature: -55°C ~ 125°C (exact match required)

The 3AB 1-R meets all substitution criteria as a direct equivalent manufactured by the same supplier with identical electrical and mechanical specifications.

Parameter Comparison

Engineering Selection Recommendations

The 3AB 1-R is the direct substitute for the obsolete 3AB 1. Both components share identical electrical and mechanical specifications, ensuring drop-in compatibility within existing circuit designs and holder assemblies. The 3AB 1-R maintains active product status with improved RoHS3 compliance, addressing regulatory requirements for new designs and manufacturing. Approval certifications (CE, CSA, cURus, PSE) confirm suitability for international applications. Minor variations in DC cold resistance (0.155 Ohms vs. 0.16 Ohms) and melting I²t (1.4 vs. 1.43) are within acceptable tolerance for ceramic cartridge fuse performance and do not affect functional equivalence.

Frequently Asked Questions (FAQ)

Q: Can the 3AB 1-R be used as a direct replacement for the 3AB 1?

A: Yes. The 3AB 1-R is electrically and mechanically equivalent to the 3AB 1. Both components have identical current rating (1 A), voltage rating (250 V AC), fuse type (cartridge, ceramic), response time (fast blow), physical dimensions (0.250" Dia x 1.252" L), and breaking capacity (35 A). No circuit modifications are required.

Q: What is the significance of the product status difference (Obsolete vs. Active)?

A: The 3AB 1 is classified as obsolete, indicating discontinued manufacturing and limited availability. The 3AB 1-R is active, ensuring reliable supply chain access and continued manufacturing support. For new designs or component replenishment, the 3AB 1-R is the appropriate selection.

Q: Are there compatibility concerns with existing fuse holders?

A: No. Both the 3AB 1 and 3AB 1-R conform to the 3AB, 3AG package standard with identical physical dimensions (1/4" x 1-1/4"). They are fully compatible with holders designed for this package specification.

Q: What is the impact of RoHS3 compliance on substitution?

A: The 3AB 1-R meets RoHS3 compliance requirements, whereas the 3AB 1 does not. For applications subject to RoHS regulations or environmental compliance mandates, the 3AB 1-R is the required selection. For legacy systems without compliance requirements, both components function identically.

Q: Are the minor differences in DC cold resistance and melting I²t significant?

A: No. The DC cold resistance difference (0.155 Ohms vs. 0.16 Ohms) and melting I²t difference (1.4 vs. 1.43) are within normal manufacturing tolerance for ceramic cartridge fuses and do not affect circuit protection performance or functional equivalence.