Littelfuse 0495040.Z Automotive Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0495040.Z is a 40A automotive fuse rated for 32V DC operation, designed for use in automotive electrical systems requiring a medium-blow response characteristic. This component is classified as obsolete, necessitating identification of active equivalent parts for ongoing procurement and system maintenance. The Auto Link package format and JCASE™ 495 series specification define the mechanical and electrical interface requirements for direct substitution.

Substiute Parts

0495040.Z

LittelfuseIn Stock: 9990495040.Z Datasheet

Current PartRFQ

0495040.ZXA

LittelfuseIn Stock: 22720495040.ZXA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the Littelfuse 0495040.Z is determined by the following critical parameters that must remain constant across equivalent parts:

• Current Rating: 40 A (exact match required)
• Package / Case: Auto Link (mechanical compatibility requirement)
• Series: JCASE™ 495 (electrical and physical interface specification)
• Breaking Capacity @ Rated Voltage: 1 kA (fault protection capability)
• Melting I²t: 3650 (thermal energy dissipation characteristic)
• Operating Temperature Range: -40°C ~ 125°C (environmental operating limits)
• Physical Dimensions: 0.555" L x 0.472" W x 1.063" H (mounting compatibility)

The primary substitute part, Littelfuse 0495040.ZXA, maintains all critical parameters while transitioning from obsolete to active product status. Voltage rating differences (DC vs. AC) and response time variations (Medium Blow vs. Slow Blow) are secondary parameters that must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The Littelfuse 0495040.ZXA is the direct active equivalent for the obsolete 0495040.Z. Selection of this substitute part is supported by:

• Product Status Transition: The substitute part maintains active product status, ensuring long-term availability and supply chain continuity.
• Regulatory Compliance: Both parts are ROHS3 compliant. The substitute part carries UR approval agency certification, providing additional regulatory validation.
• Mechanical Compatibility: Identical Auto Link package format and JCASE™ 495 series specification ensure direct physical and electrical interface compatibility.
• Electrical Performance: Matching current rating (40 A), breaking capacity (1 kA), and melting I²t (3650) preserve fault protection characteristics.

Applications requiring DC-specific voltage ratings or medium-blow response characteristics must evaluate the voltage rating difference (32 V DC vs. 32 V AC) and response time variation (Medium Blow vs. Slow Blow) against circuit design specifications.

Frequently Asked Questions (FAQ)

Q: Can the 0495040.ZXA directly replace the 0495040.Z in existing automotive systems?

A: Direct mechanical and electrical interface compatibility is confirmed through matching Auto Link package format, JCASE™ 495 series specification, current rating (40 A), and physical dimensions. Voltage rating and response time differences must be evaluated against specific circuit requirements.

Q: What is the significance of the voltage rating difference between the main part and substitute?

A: The main part is rated for 32 V DC operation, while the substitute is rated for 32 V AC operation. Both parts are suitable for automotive electrical systems operating within these voltage specifications. Application voltage characteristics must be confirmed before substitution.

Q: How does the response time difference affect fuse selection?

A: The main part features a medium-blow response characteristic, while the substitute features a slow-blow response. Response time determines the fuse's reaction speed to overcurrent conditions. Circuit design specifications must define the required response characteristic for proper protection.

Q: What is the impact of the DC cold resistance difference?

A: The main part specifies 0.0013 Ohms DC cold resistance, while the substitute specifies 1.3 Ohms. This difference affects resistive heating characteristics under normal operating conditions. Circuit thermal analysis may be required to confirm compatibility in applications sensitive to resistive losses.

Q: Are both parts suitable for the same automotive applications?

A: Both parts share identical current rating (40 A), breaking capacity (1 kA), melting I²t (3650), operating temperature range (-40°C ~ 125°C), and physical dimensions. Application-specific requirements regarding voltage type (AC vs. DC), response time (medium vs. slow blow), and resistance characteristics must be confirmed.

Q: What certifications and compliance standards apply to these parts?

A: Both parts are ROHS3 compliant. The substitute part carries UR approval agency certification. The main part does not specify an approval agency. Regulatory requirements for the target application must be confirmed.