FWA-125B Equivalent & Substitute Parts

Part Overview

The FWA-125B is a 125A cartridge fuse manufactured by Eaton - Bussmann Electrical Division, rated for 150 VAC and 150 VDC operation with bolt mount configuration. This component is designed for electrical and industrial applications requiring high breaking capacity (100kA AC, 20kA DC) and is currently in active production status. Substitute parts are identified when equivalent electrical ratings, mechanical compatibility, and regulatory compliance can be maintained across alternative manufacturers.

Substiute Parts

FWA-125B

Eaton - Bussmann Electrical DivisionIn Stock: 1005FWA-125B Datasheet

Current PartRFQ

L15S125.T

Littelfuse Inc.In Stock: 962L15S125.T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FWA-125B is determined by the following critical parameters:

• Current Rating: Must be 125A
• Voltage Rating - AC: Must be 150 VAC minimum
• Voltage Rating - DC: Must be 150 VDC minimum
• Fuse Type: Must be Cartridge
• Mounting Type: Must be Bolt Mount
• Package / Case: Must be Cylindrical with Blade Terminal (Bolt)
• Physical Dimensions: Must be compatible with 1.000" Dia x 1.156" L envelope
• Breaking Capacity: Must maintain 100kA AC and 20kA DC minimum

The L15S125.T from Littelfuse Inc. meets the primary electrical and mechanical requirements with the exception of DC voltage rating (100 VDC vs. 150 VDC required). This variance must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

FWA-125B (Eaton - Bussmann): Select this part for applications requiring 150 VDC operation. The component maintains active production status with CE and UR approvals. RoHS compliance is confirmed.

L15S125.T (Littelfuse - POWR-GARD® L15S): This substitute is suitable for applications operating at 100 VDC or lower. The part is actively produced with CE, CSA, and UR certifications. ROHS3 compliance exceeds baseline RoHS requirements. Physical dimensions are compatible within tolerance. The Fast Blow response characteristic should be verified against application requirements.

Selection between these parts must be based on the specific DC voltage requirement of the application circuit. If 150 VDC operation is required, the FWA-125B is the appropriate choice. If the application operates at 100 VDC or lower, the L15S125.T provides equivalent functionality with additional CSA certification.

Frequently Asked Questions (FAQ)

Q: Can the L15S125.T replace the FWA-125B in all applications?

A: No. The L15S125.T has a maximum DC voltage rating of 100 VDC, while the FWA-125B is rated for 150 VDC. Substitution is valid only for applications operating at 100 VDC or lower.

Q: Are the physical dimensions compatible?

A: Yes. Both parts are cylindrical with 1.000" diameter. The length difference (1.156" vs. 1.157") is within standard manufacturing tolerance and does not affect mechanical compatibility in bolt mount applications.

Q: What is the difference in response time between these parts?

A: The L15S125.T is specified as Fast Blow. The FWA-125B response time is not provided in the available data. Application requirements for response characteristics must be confirmed before substitution.

Q: Are both parts RoHS compliant?

A: Yes. The FWA-125B is RoHS Compliant. The L15S125.T is ROHS3 Compliant, which represents an updated compliance standard.

Q: Which certifications apply to each part?

A: FWA-125B holds CE and UR approvals. L15S125.T holds CE, CSA, and UR approvals. Both meet the common CE and UR requirements.

Q: What is the breaking capacity for both parts?

A: Both parts maintain 100kA AC and 20kA DC breaking capacity at rated voltage, meeting equivalent performance specifications.