RLD60P250XFF Equivalent & Substitute Parts

Part Overview

The RLD60P250XFF is a polymeric PTC resettable fuse manufactured by Littelfuse Inc., part of the POLY-FUSE® RLD60 series. This component is rated for 60V maximum voltage with a 2.5A hold current and is designed for through-hole radial mounting in disc configuration. The product is currently obsolete, making identification of suitable substitute components essential for ongoing system support and component procurement.

Substiute Parts

RLD60P250XFF

Littelfuse Inc.In Stock: 785RLD60P250XFF Datasheet

Current PartRFQ

60R250XMR

Littelfuse Inc.In Stock: 245460R250XMR Datasheet

DirectRFQ

72R250XMR

LittelfuseIn Stock: 311372R250XMR Datasheet

DirectRFQ

RXEF250-AP

Littelfuse Inc.In Stock: 956RXEF250-AP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the RLD60P250XFF is determined by strict alignment of the following electrical and mechanical parameters:

Critical Matching Parameters:

• Voltage - Max: Must be ≥ 60V
• Current - Hold (Ih) (Max): Must be 2.5 A
• Current - Trip (It): Must be 5 A
• Resistance - Initial (Ri) (Min): Must be 50 mOhms
• Resistance - Post Trip (R1) (Max): Must be ≤ 130 mOhms
• Operating Temperature Range: Must support -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: Radial, Disc
• Lead Spacing: 0.402" (10.20mm)

Identified Substitutes:

Group 1 - Direct Electrical Match (60V Rating):

• 60R250XMR (Littelfuse POLY-FUSE® 60R series, Active status)

Group 2 - Higher Voltage Rating (72V Rating):

• 72R250XMR (Littelfuse POLY-FUSE® 72R series, Active status)
• RXEF250-AP (Littelfuse PolySwitch® RXEF series, Active status)

All substitute parts maintain identical electrical performance characteristics (hold current, trip current, resistance values, and time to trip) while differing in voltage rating and physical dimensions. The 72V-rated alternatives provide enhanced voltage margin for applications operating at or near 60V nominal levels.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: 60R250XMR

The 60R250XMR is the optimal substitute for the obsolete RLD60P250XFF. This component maintains identical voltage rating (60V), all electrical parameters, and thermal operating range. The 60R250XMR is in active production status with established supply availability (2374 pcs in stock). Both components carry cURus and TUV certifications and are ROHS3 compliant. The primary design consideration is the reduced diameter (0.785" vs. 0.839"), which may require PCB layout verification for clearance compatibility.

Secondary Recommendations: 72R250XMR and RXEF250-AP

The 72R250XMR and RXEF250-AP are suitable alternatives for applications where higher voltage margin is beneficial. Both maintain identical electrical performance and operating temperature range. The 72R250XMR offers continuity within the POLY-FUSE® product family, while the RXEF250-AP provides expanded certification coverage (CQC, CSA, TUV, UL) for applications requiring broader regulatory approval. Physical dimensions differ slightly from the original component; PCB layout verification is required.

Compliance Considerations:

All substitute parts are ROHS3 compliant and carry appropriate regulatory certifications. The RXEF250-AP provides the broadest certification scope (CQC, CSA, TUV, UL) compared to the original component (cURus, TUV).

Frequently Asked Questions (FAQ)

Q: Can the 60R250XMR directly replace the RLD60P250XFF without circuit modification?

A: The 60R250XMR is electrically equivalent and maintains all critical performance parameters. Physical dimensions differ slightly (diameter reduced from 0.839" to 0.785"), requiring verification that PCB footprint and clearance accommodate the smaller component. Lead spacing remains identical at 0.402" (10.20mm).

Q: What is the difference between the 60V and 72V rated substitutes?

A: The 72R250XMR and RXEF250-AP are rated for 72V maximum voltage compared to the original 60V rating. All other electrical parameters (hold current, trip current, resistance values, time to trip) are identical. The higher voltage rating provides additional safety margin in applications operating at or near 60V nominal levels. Selection depends on circuit voltage requirements and design margin preferences.

Q: Are there mechanical compatibility concerns with the substitute parts?

A: All substitute parts maintain through-hole radial disc mounting configuration and identical lead spacing (0.402" / 10.20mm for 60R250XMR and 72R250XMR; 0.400" / 10.15mm for RXEF250-AP). Physical diameter and height vary slightly. PCB layout verification is required to confirm clearance compatibility, particularly for the reduced diameter of the 60R and 72R series compared to the original RLD60P250XFF.

Q: Which substitute offers the best supply availability?

A: The 72R250XMR offers the highest current inventory (3004 pcs), followed by the 60R250XMR (2374 pcs) and RXEF250-AP (905 pcs). All three are in active production status.

Q: Do all substitutes maintain the same regulatory certifications?

A: The 60R250XMR and 72R250XMR carry cURus and TUV certifications, matching the original component. The RXEF250-AP provides expanded certification coverage (CQC, CSA, TUV, UL). All are ROHS3 compliant. Application-specific regulatory requirements should determine certification selection.

Q: What is the impact of the different series designations (POLY-FUSE® vs. PolySwitch®)?

A: Both POLY-FUSE® and PolySwitch® are Littelfuse polymeric PTC resettable fuse product lines. The electrical and thermal performance characteristics are identical for the specified ratings. Series designation reflects product family organization and does not affect functional compatibility for applications matching the electrical parameters.