Equivalent & Substitute Parts for RLD60P040XF

Part Overview

The RLD60P040XF is a polymeric PTC resettable fuse manufactured by Littelfuse Inc., rated for 60V maximum voltage and 400 mA hold current. This component is classified as obsolete, which necessitates identification of active equivalent and substitute parts for ongoing design support and procurement. The RLD60P040XF belongs to the POLY-FUSE® RLD60 series and is designed for through-hole radial mounting in disc configuration.

Substiute Parts

RLD60P040XF

Littelfuse Inc.In Stock: 730RLD60P040XF Datasheet

Current PartRFQ

RXEF040-AP

Littelfuse Inc.In Stock: 1067RXEF040-AP Datasheet

DirectRFQ

60R040XU

Littelfuse Inc.In Stock: 103460R040XU Datasheet

MFR RecommendedRFQ

60R040XPR

Littelfuse Inc.In Stock: 654960R040XPR Datasheet

Parametric EquivalentRFQ

72R040XPR

LittelfuseIn Stock: 281872R040XPR Datasheet

Parametric EquivalentRFQ

MF-R040

Bourns Inc.In Stock: 11844MF-R040 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RLD60P040XF is determined by the following critical parameters:

• Voltage rating (60V or higher)
• Hold current rating (400 mA)
• Trip current (800 mA)
• Time to trip (3.8 s)
• Initial resistance (550 mOhms minimum)
• Post-trip resistance (1.29 Ohms maximum)
• Operating temperature range (-40°C ~ 85°C)
• Through-hole radial disc mounting configuration
• Lead spacing (5.10mm nominal)

Substitute parts are grouped into three categories:

Direct Manufacturer Equivalent (Same Manufacturer, Different Series): RXEF040-AP operates at 72V maximum voltage, providing higher voltage margin while maintaining identical hold current, trip current, and time-to-trip specifications. This part is from the PolySwitch® RXEF series and is active with current production status.

Manufacturer Recommended Equivalents (Same Manufacturer, Same Voltage): 60R040XU and 60R040XPR are both from the Littelfuse POLY-FUSE® 60R series, matching the original 60V rating and all electrical parameters. These parts differ only in packaging (bulk versus cut tape) and compliance status.

Parametric Equivalents (Alternative Manufacturers, Matched Specifications): 72R040XPR (Littelfuse POLY-FUSE® 72R series) and MF-R040 (Bourns Multifuse® MF-R series) provide equivalent electrical performance at 60V or 72V ratings with matched hold current, trip current, and thermal characteristics.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Same Voltage Rating): 60R040XU and 60R040XPR are the primary substitutes, both maintaining the 60V maximum voltage rating of the original RLD60P040XF. Both parts are active products with ROHS3 compliance and current production inventory. 60R040XPR is available in cut tape packaging with the highest inventory level (6512 pcs), while 60R040XU is supplied in bulk packaging. Both carry cURus and TUV approvals matching the original part's certification profile.

For Higher Voltage Margin Applications: 72R040XPR and RXEF040-AP provide 72V maximum voltage ratings, offering 20% additional voltage headroom over the original 60V specification. Both maintain identical electrical performance parameters (400 mA hold current, 800 mA trip current, 3.8 s trip time). 72R040XPR is from the Littelfuse POLY-FUSE® 72R series with cURus and TUV approvals. RXEF040-AP is from the PolySwitch® RXEF series with expanded certifications (CQC, CSA, TUV, UL) and MSL rating of 1 (Unlimited), indicating superior moisture handling characteristics.

For Cross-Manufacturer Substitution: MF-R040 from Bourns Multifuse® MF-R series provides equivalent electrical performance at 60V with matched hold current, trip current, and thermal specifications. Initial resistance is 520 mOhms (slightly lower than the 550 mOhms minimum of the original), and post-trip resistance remains at 1.29 Ohms maximum. Physical dimensions are nominally equivalent (0.291" diameter versus 0.299" for the original), with identical lead spacing and height. MF-R040 carries ROHS3 compliance and cURus/TUV approvals with 11793 pcs available inventory.

Compliance Consideration: All active substitute parts are ROHS3 compliant, whereas the original RLD60P040XF is RoHS non-compliant. This is a significant advantage for new designs and systems requiring regulatory compliance.

Frequently Asked Questions (FAQ)

Q: Can 60R040XU or 60R040XPR be used as direct drop-in replacements for RLD60P040XF?

A: Yes. Both parts maintain identical electrical specifications (60V, 400 mA hold current, 800 mA trip current, 3.8 s trip time), matching physical dimensions (0.299" diameter x 0.122" thickness), and lead spacing (0.201" / 5.10mm). The primary difference is packaging format (bulk versus cut tape) and compliance status (ROHS3 compliant versus non-compliant).

Q: What is the difference between 60R040XPR and 72R040XPR?

A: Both parts are from the Littelfuse POLY-FUSE® series with identical electrical performance and physical dimensions. The primary difference is maximum voltage rating: 60R040XPR is rated for 60V, while 72R040XPR is rated for 72V. The 72V variant provides additional voltage margin for applications operating near the upper voltage limit of the original specification.

Q: Is RXEF040-AP compatible with the original RLD60P040XF circuit?

A: RXEF040-AP is electrically compatible, maintaining 400 mA hold current, 800 mA trip current, and 3.8 s trip time. However, it operates at 72V maximum voltage (versus 60V for the original). Physical dimensions are nominally equivalent with a thickness of 0.118" (3.00mm) versus 0.122" (3.10mm) for the original, and lead spacing of 0.199" (5.05mm) versus 0.201" (5.10mm). These minor dimensional variations are within typical PCB tolerance ranges for through-hole radial components.

Q: Can MF-R040 from Bourns be used instead of Littelfuse parts?

A: Yes. MF-R040 provides equivalent electrical performance with 60V rating, 400 mA hold current, 800 mA trip current, and 3.8 s trip time. Physical dimensions are nominally equivalent (0.291" diameter versus 0.299" for the original), with identical lead spacing (0.201" / 5.10mm) and height. Initial resistance is 520 mOhms (slightly lower than the 550 mOhms minimum specification), which is within acceptable tolerance for PTC resettable fuse applications.

Q: What packaging options are available for these substitute parts?

A: 60R040XU is supplied in bulk packaging. 60R040XPR and 72R040XPR are supplied in cut tape (CT) packaging. RXEF040-AP is supplied in cut tape (CT) packaging. MF-R040 is supplied in bulk packaging. Selection depends on procurement volume and assembly process requirements.

Q: Are all substitute parts RoHS compliant?

A: Yes. All active substitute parts (60R040XU, 60R040XPR, 72R040XPR, RXEF040-AP, and MF-R040) are ROHS3 compliant. The original RLD60P040XF is RoHS non-compliant, making the substitutes advantageous for new designs and systems requiring regulatory compliance.