FWP-40B Equivalent & Substitute Parts

Part Overview

The FWP-40B is a 40A cartridge fuse rated for 700 VAC and 700 VDC operation, manufactured by Eaton - Bussmann Electrical Division. This bolt-mount fuse is designed for electrical and industrial applications requiring high voltage protection. The part maintains active product status with 826 units in current inventory. Substitute parts are identified when equivalent electrical ratings and mechanical compatibility are maintained across the critical parameters of current rating, voltage ratings, mounting type, and physical dimensions.

Substiute Parts

FWP-40B

Eaton - Bussmann Electrical DivisionIn Stock: 925FWP-40B Datasheet

Current PartRFQ

L70S040.T

Littelfuse Inc.In Stock: 1073L70S040.T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

The L70S040.T from Littelfuse Inc. is identified as a substitute based on the following critical parameters:

• Current Rating: Both parts are rated 40A
• Voltage Rating - AC: Both parts are rated 700 VAC
• Fuse Type: Both are cartridge fuses
• Mounting Type: Both use bolt mount configuration
• Package / Case: Both feature cylindrical design with blade terminal (bolt)
• Approval Agency: Both hold CE, CSA, and UR certifications
• RoHS Compliance: Both meet RoHS standards

The L70S040.T maintains functional equivalence for applications requiring 40A protection at 700 VAC. The DC voltage rating difference (650 VDC vs. 700 VDC) and physical dimension variations are noted in the parameter comparison table below.

Parameter Comparison

Engineering Selection Recommendations

Both the FWP-40B and L70S040.T maintain active product status and hold equivalent regulatory certifications (CE, CSA, UR). Selection between these parts should be based on the specific application requirements:

The FWP-40B is suitable for applications requiring the full 700 VDC rating and 50kA DC breaking capacity. The L70S040.T is suitable for applications operating at 650 VDC or lower, with 20kA DC breaking capacity. Physical dimension differences must be verified against mounting cavity specifications, as the L70S040.T has a larger diameter (1.000" vs. 0.813") and length (2.874" vs. 2.750").

Both parts comply with current RoHS standards and maintain equivalent AC voltage and current ratings for 700 VAC, 40A applications.

Frequently Asked Questions (FAQ)

Q: Can the L70S040.T replace the FWP-40B in all applications?

A: The L70S040.T is suitable for replacement in applications operating at 650 VDC or lower. If your application requires the full 700 VDC rating, the FWP-40B is the appropriate choice. Physical dimensions must also be verified for mounting compatibility.

Q: What is the significance of the different DC voltage ratings?

A: The FWP-40B is rated 700 VDC while the L70S040.T is rated 650 VDC. This difference affects the maximum DC voltage the fuse can safely interrupt. Applications operating above 650 VDC require the FWP-40B.

Q: Are there physical dimension compatibility concerns?

A: Yes. The L70S040.T has a larger diameter (1.000" vs. 0.813") and slightly longer length (2.874" vs. 2.750"). Verify that your mounting cavity accommodates these dimensions before substitution.

Q: Do both parts have the same breaking capacity?

A: Both parts have 200kA AC breaking capacity. However, the DC breaking capacity differs: FWP-40B provides 50kA DC while L70S040.T provides 20kA DC. Select based on your circuit's fault current requirements.

Q: Are regulatory certifications equivalent?

A: Yes. Both parts hold CE, CSA, and UR certifications. Both comply with RoHS standards, with the L70S040.T meeting the ROHS3 specification.

Q: What does "Fast Blow" response time mean for the L70S040.T?

A: Fast Blow indicates the fuse responds quickly to overcurrent conditions. The FWP-40B response time is not specified in the provided data. Verify response time requirements for your specific application.