RXE050S Equivalent & Substitute Parts

Part Overview

The RXE050S is a polymeric PTC resettable fuse manufactured by Littelfuse Inc., rated for 72V maximum voltage with a 500 mA hold current. This component is classified as obsolete, which necessitates identification of active equivalent parts for ongoing design support and procurement. The RXE050S belongs to the PolySwitch® RXE series and is designed for through-hole radial mounting applications requiring automatic overcurrent protection with self-recovery capability.

Substiute Parts

RXE050S

Littelfuse Inc.In Stock: 1050RXE050S Datasheet

Current PartRFQ

RXEF050S

LittelfuseIn Stock: 9168RXEF050S Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RXE050S is determined by electrical and mechanical parameter equivalence. The critical parameters defining substitutability are:

• Voltage rating: 72V maximum
• Hold current: 500 mA maximum
• Trip current: 1 A
• Maximum current: 40 A
• Time to trip: 4 seconds
• Initial resistance: 500 mOhms minimum
• Post-trip resistance: 1.17 Ohms maximum
• Mounting configuration: Through-hole radial
• Physical dimensions: 0.311" diameter × 0.118" thickness with 0.199" lead spacing

The RXEF050S meets all specified electrical and mechanical parameters, providing direct functional equivalence for the obsolete RXE050S.

Parameter Comparison

Engineering Selection Recommendations

The RXEF050S is the direct active equivalent for the obsolete RXE050S. Both components share identical electrical specifications and physical dimensions, ensuring pin-for-pin and functional compatibility in existing circuit designs.

The RXEF050S offers additional advantages for new designs: it maintains active product status with Littelfuse, carries ROHS3 compliance compared to the non-compliant RXE050S, and includes specified operating temperature range (-40°C to 85°C). The RXEF050S also provides expanded regulatory approvals including CQC certification in addition to CSA, TUV, and UL certifications.

For applications currently using the RXE050S, direct substitution with RXEF050S requires no circuit modifications or re-qualification, as all critical electrical and mechanical parameters remain unchanged.

Frequently Asked Questions (FAQ)

Q: Can RXEF050S directly replace RXE050S in existing designs?

A: Yes. The RXEF050S provides identical electrical performance and physical dimensions. No circuit modifications are required for direct substitution.

Q: What are the key differences between RXE050S and RXEF050S?

A: The primary differences are product status (RXE050S is obsolete; RXEF050S is active), RoHS compliance (RXEF050S is ROHS3 compliant), and regulatory certifications (RXEF050S includes CQC approval). Electrical and mechanical specifications are identical.

Q: Are there any packaging differences?

A: The RXE050S is specified with "-" packaging notation, while RXEF050S is supplied in bag packaging. Both components use identical radial disc form factors with 0.199" lead spacing.

Q: What is the operating temperature range for these components?

A: The RXE050S does not specify an operating temperature range. The RXEF050S operates across -40°C to 85°C, which covers standard industrial and commercial temperature requirements.

Q: Are both parts certified by the same regulatory bodies?

A: Both parts carry CSA, TUV, and UL certifications. The RXEF050S additionally includes CQC certification, providing broader international regulatory coverage.