FNW-20 Equivalent & Substitute Parts Reference

Part Overview

The FNW-20 is a 20A 250VAC cartridge fuse manufactured by Eaton - Bussmann Electrical Division, classified as a slow-blow (5AG) fuse in a 10mm x 38mm midget package format. This component is designed for electrical and industrial applications requiring overcurrent protection in AC circuits rated at 250 volts. The FNW-20 carries an obsolete product status, making identification of functionally equivalent alternatives necessary for ongoing system maintenance and component procurement.

Substiute Parts

FNW-20

Eaton - Bussmann Electrical DivisionIn Stock: 1133FNW-20 Datasheet

Current PartRFQ

FNM-20

Eaton - Bussmann Electrical DivisionIn Stock: 839FNM-20 Datasheet

DirectRFQ

0FLM020.T

Littelfuse Inc.In Stock: 10660FLM020.T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the FNW-20 are identified based on strict electrical and mechanical parameter alignment. The primary substitution criteria are:

• Current Rating: 20A (exact match required)
• Voltage Rating - AC: 250 VAC (exact match required)
• Response Time: Slow Blow (exact match required)
• Fuse Class: 5AG / CC (exact match required)
• Package / Case: 10mm x 38mm Midget format (exact match required)
• Breaking Capacity: 10kA (exact match required)
• Mounting Type: Requires Holder (exact match required)

Two substitute parts meet these criteria:

1. FNM-20 (Eaton - Bussmann Electrical Division) - Direct manufacturer equivalent with active product status
2. 0FLM020.T (Littelfuse Inc.) - Cross-manufacturer equivalent with extended voltage rating capability (includes 125 VDC rating in addition to 250 VAC)

Parameter Comparison

Engineering Selection Recommendations

FNM-20 is the primary substitute for the obsolete FNW-20. Both components are manufactured by Eaton - Bussmann Electrical Division and share identical electrical specifications (20A, 250 VAC, slow-blow response, 10kA breaking capacity). The FNM-20 maintains active product status and carries the same regulatory approvals (CE, CSA, UL). Dimensional tolerances are within acceptable limits for holder compatibility. The FNM-20 is ROHS3 compliant, addressing modern environmental compliance requirements.

0FLM020.T (Littelfuse Inc.) serves as a secondary cross-manufacturer substitute. This component meets all primary electrical and mechanical requirements for 250 VAC AC circuits. The addition of 125 VDC rating capability provides extended application flexibility for dual-voltage systems. The 0FLM020.T carries CSA, PSE, QPL, and UL approvals. Dimensional specifications align with standard 5AG midget fuse holder requirements. ROHS3 compliance is confirmed.

Selection between FNM-20 and 0FLM020.T depends on supply chain availability, manufacturer preference, and whether DC voltage capability is required for the application circuit.

Frequently Asked Questions (FAQ)

Q: Can FNM-20 be used as a direct replacement for FNW-20?

A: Yes. The FNM-20 meets all electrical and mechanical specifications of the FNW-20. Both are 20A, 250 VAC, slow-blow cartridge fuses in 5AG 10mm x 38mm format with 10kA breaking capacity. Dimensional differences (38.10mm vs 38.00mm length) are within standard holder tolerances.

Q: What is the difference between FNM-20 and 0FLM020.T?

A: Both components are electrically equivalent for 250 VAC AC applications. The 0FLM020.T includes an additional 125 VDC rating, making it suitable for dual-voltage circuits. FNM-20 is manufactured by Eaton - Bussmann, while 0FLM020.T is manufactured by Littelfuse Inc. Regulatory approvals differ slightly between manufacturers.

Q: Are all three fuses compatible with the same holder?

A: Yes. All three components use the 5AG midget cartridge format (10mm x 38mm). Dimensional specifications are within acceptable tolerances for standard 5AG fuse holders. Verify holder specifications for your specific application.

Q: Does the FNW-20 obsolescence affect availability of substitutes?

A: No. Both FNM-20 and 0FLM020.T carry active product status and are in current production. Inventory availability is confirmed for both alternatives.

Q: Are FNM-20 and 0FLM020.T ROHS compliant?

A: Yes. Both FNM-20 and 0FLM020.T are ROHS3 compliant, meeting current environmental regulations for electrical components.

Q: Which substitute should I select for new designs?

A: For new designs, either FNM-20 or 0FLM020.T is acceptable. FNM-20 maintains manufacturer continuity with the original Eaton - Bussmann product line. 0FLM020.T offers extended DC voltage capability if the application requires dual-voltage protection. Verify regulatory approval requirements for your specific market and application.