Littelfuse 02040603Z Automotive Relay - Equivalent & Substitute Parts

Part Overview

The Littelfuse 02040603Z is an automotive SPDT relay designed for 12VDC switching applications with a 20A contact rating. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations. The MICRO series relay features non-latching coil operation, socketable mounting, and plug-in termination suitable for automotive electrical systems.

Substiute Parts

02040603Z

Littelfuse Inc.In Stock: 103002040603Z Datasheet

Current PartRFQ

CM1-12V

Panasonic Electric WorksIn Stock: 5761CM1-12V Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Littelfuse 02040603Z is determined by the following critical parameters:

Primary Compatibility Criteria:

• Coil voltage: 12VDC
• Contact form: SPDT (1 Form C)
• Coil type: Non Latching
• Mounting type: Socketable
• Termination style: Plug In

Secondary Compatibility Criteria:

• Contact rating current: minimum 20A
• Switching voltage: 12VDC nominal or compatible range
• RoHS3 compliance
• MSL rating: 1 (Unlimited)

The Panasonic Electric Works CM1-12V meets all primary criteria and exceeds secondary criteria with a 35A contact rating, providing enhanced current capacity while maintaining identical coil voltage, contact form, mounting configuration, and termination style.

Parameter Comparison

Engineering Selection Recommendations

The Panasonic Electric Works CM1-12V is a direct functional substitute for the obsolete Littelfuse 02040603Z. Both components share identical coil voltage (12VDC), contact form (SPDT), mounting configuration (socketable), and termination style (plug-in). Both maintain ROHS3 compliance and MSL rating 1 (Unlimited).

The CM1-12V is currently in active production status, ensuring long-term availability and supply chain continuity. The increased contact rating (35A versus 20A) provides additional design margin without introducing incompatibility. The switching voltage specification (14VDC nominal) encompasses the original 12VDC nominal specification, maintaining operational compatibility within automotive electrical system parameters.

Frequently Asked Questions (FAQ)

Q: Can the Panasonic CM1-12V directly replace the Littelfuse 02040603Z in existing applications?

A: Yes. Both relays share identical coil voltage (12VDC), contact form (SPDT), mounting type (socketable), and termination style (plug-in). The socketable mounting and plug-in termination ensure mechanical and electrical compatibility without circuit board modifications.

Q: What is the significance of the higher 35A contact rating on the CM1-12V compared to the 20A rating of the 02040603Z?

A: The CM1-12V's 35A contact rating exceeds the original 20A specification, providing additional current-carrying capacity. This represents an enhancement rather than a limitation, allowing the substitute to handle equal or greater switching loads within the same 12VDC coil voltage framework.

Q: Are there compliance differences between the two parts?

A: Both components are ROHS3 compliant and carry MSL rating 1 (Unlimited). Compliance certifications are equivalent, supporting use in regulated automotive applications.

Q: Why is the Littelfuse 02040603Z listed as obsolete?

A: Obsolete status indicates the part is no longer manufactured by Littelfuse. The Panasonic CM1-12V, with active production status, provides continuity for applications requiring SPDT 12VDC automotive relay functionality.

Q: Does the socketable mounting configuration affect substitution compatibility?

A: No. Both the original and substitute parts feature socketable mounting with plug-in termination, ensuring direct compatibility with existing relay sockets and circuit board layouts without requiring hardware modifications.