Littelfuse 0257004.L Automotive Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0257004.L is a 4A 32VDC automotive blade fuse in ATO/ATC package format, designed for automotive electrical circuit protection. This part carries an Obsolete product status, making identification of active equivalent components essential for ongoing maintenance, repair, and new design applications. The obsolescence necessitates sourcing from currently active substitute parts that maintain identical electrical and mechanical specifications.

Substiute Parts

0257004.L

Littelfuse Inc.In Stock: 10350257004.L Datasheet

Current PartRFQ

0287004.PXCN

Littelfuse Inc.In Stock: 793650287004.PXCN Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The Littelfuse 0287004.PXCN qualifies as a direct substitute for the 0257004.L based on the following critical parameters:

• Current Rating: Both parts rated at 4 A
• Voltage Rating (DC): Both rated at 32 V
• Fuse Type: Both are automotive blade fuses
• Package / Case: Both use Blade, ATO/ATC format
• Breaking Capacity: Both rated at 1 kA @ rated voltage
• Melting I²t: Both have melting I²t value of 14
• Operating Temperature: Both operate across -40°C ~ 105°C
• DC Cold Resistance: Both measure 0.0228 Ohms
• RoHS Compliance: Both are ROHS3 Compliant

The substitute part differs in product status (Active vs. Obsolete) and response time classification (Fast Blow), with dimensional tolerances within acceptable manufacturing variation.

Parameter Comparison

Engineering Selection Recommendations

The Littelfuse 0287004.PXCN is the appropriate substitute for the obsolete 0257004.L. Selection is based on:

• Electrical Equivalence: Identical current rating, voltage rating, breaking capacity, and melting I²t characteristics ensure functional interchangeability in automotive circuit protection applications.
• Mechanical Compatibility: Both parts use the ATO/ATC blade package format, ensuring physical compatibility with standard automotive fuse holders.
• Thermal Performance: Matching operating temperature range (-40°C ~ 105°C) and DC cold resistance (0.0228 Ohms) confirm thermal and electrical performance equivalence.
• Compliance Status: Both parts maintain ROHS3 compliance, supporting regulatory requirements for automotive applications.
• Active Availability: The substitute part carries Active product status with substantial inventory availability, ensuring reliable sourcing for replacement and new applications.

Frequently Asked Questions (FAQ)

Q: Can the 0287004.PXCN directly replace the 0257004.L in existing automotive circuits?

A: Yes. Both parts share identical electrical ratings (4A, 32VDC), breaking capacity (1kA), melting I²t (14), and operate across the same temperature range (-40°C ~ 105°C). The ATO/ATC blade package format ensures physical compatibility with standard automotive fuse holders.

Q: What is the difference between the ATO® and ATOF® series designations?

A: The series designation reflects manufacturer product line classification. Both parts maintain identical electrical and mechanical specifications for automotive blade fuse applications. The ATOF® designation on the substitute part indicates Fast Blow response time, which is not specified for the obsolete part.

Q: Are there any dimensional differences between these parts?

A: Dimensional measurements show minor variations within manufacturing tolerance: the substitute part measures 0.752" L x 0.201" W x 0.484" H compared to 0.750" L x 0.200" W x 0.480" H for the main part. These variations are within acceptable tolerances for ATO/ATC blade fuse specifications and do not affect holder compatibility.

Q: Does the Fast Blow response time of the substitute part affect circuit protection performance?

A: Response time classification describes the fuse's thermal response characteristics. Both parts share identical melting I²t values (14), which determine the actual protection threshold. The Fast Blow designation on the substitute part indicates faster thermal response but does not alter the fundamental protection characteristics for the specified 4A rating.

Q: Are both parts RoHS compliant?

A: Yes. Both the 0257004.L and 0287004.PXCN are ROHS3 Compliant, meeting regulatory requirements for automotive applications.

Q: What is the DC cold resistance specification, and why is it identical in both parts?

A: DC cold resistance (0.0228 Ohms) measures the fuse element's electrical resistance at room temperature. Identical values ensure equivalent voltage drop and thermal characteristics during normal circuit operation, confirming functional equivalence.