A6D40R Equivalent & Substitute Parts

Part Overview

The A6D40R is a 600V 40A RK1 TD fuse manufactured by Mersen USA Newburyport-MA L.L.C. This cartridge fuse is designed for electrical and industrial applications requiring time-delay (slow-blow) response characteristics at 600VAC ratings. The part is currently active in production with 862 units in stock. Finding equivalent substitute parts may be necessary due to supply chain considerations, lead time requirements, or specific application needs while maintaining identical electrical and mechanical performance.

Substiute Parts

A6D40R

Mersen USA Newburyport-MA L.L.C.In Stock: 953A6D40R Datasheet

Current PartRFQ

LSRK040.T

Littelfuse Inc.In Stock: 961LSRK040.T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the A6D40R must satisfy the following critical parameters to ensure functional equivalence:

• Current Rating: 40A (exact match required)
• Voltage Rating - AC: 600VAC (exact match required)
• Fuse Class: RK1 (exact match required)
• Response Time: Time Delay / Slow Blow (exact match required)
• Mounting Type: Cartridge format requiring holder (exact match required)

The LSRK040.T from Littelfuse Inc. meets all substitution criteria. This part maintains identical electrical ratings (40A, 600VAC) and fuse class (RK1) with matching time-delay response characteristics. Both parts are cartridge-type fuses requiring a compatible holder for installation.

Parameter Comparison

Engineering Selection Recommendations

Both the A6D40R and LSRK040.T are active production parts suitable for 40A, 600VAC RK1 applications. The LSRK040.T offers additional compliance benefits with ROHS3 certification and extended DC voltage capability (300VDC), making it suitable for applications requiring higher environmental or regulatory standards. Selection between these parts should be based on specific application requirements, holder compatibility, and compliance mandates for the end application. Both parts carry relevant industrial certifications (UL, CSA, CE) appropriate for electrical and industrial use.

Frequently Asked Questions (FAQ)

Q: Can LSRK040.T directly replace A6D40R in existing installations?

A: Yes, provided the fuse holder is compatible with the cartridge dimensions (1.063" Dia x 5.500" L). Both parts are RK1 class cartridge fuses with identical 40A, 600VAC ratings and time-delay response characteristics.

Q: What is the significance of RK1 fuse class for substitution?

A: RK1 class designation defines specific electrical performance characteristics including current-limiting behavior and breaking capacity. Substitutes must maintain RK1 class to ensure equivalent protection and performance in the circuit.

Q: Does the LSRK040.T's ROHS3 compliance affect compatibility?

A: ROHS3 compliance indicates the substitute part meets environmental standards but does not affect electrical or mechanical compatibility. The A6D40R's RoHS non-compliant status may be relevant only if the end application has specific regulatory requirements.

Q: Are there dimensional differences between these cartridge fuses?

A: The LSRK040.T dimensions are specified as 1.063" Dia x 5.500" L. Verify that the A6D40R uses identical dimensions to ensure proper fit in existing fuse holders. Cartridge fuse holders are typically standardized for RK1 class, but physical verification is recommended.

Q: What does "Time Delay" or "Slow Blow" response mean for substitution purposes?

A: Time-delay fuses tolerate temporary inrush currents without nuisance opening, making them suitable for circuits with startup transients. Both parts provide identical response characteristics, ensuring equivalent circuit protection behavior.