RXEF300K

Ptc Resettable Fuses Overview

The Littelfuse RXEF300K is a PolySwitch radial leaded PPTC resettable fuse designed for overcurrent protection. It features a 3 A hold current and a 6 A trip current, operating at a maximum voltage of 72 V. The device withstands a maximum fault current of 40 A and exhibits a maximum resistance of 100 mOhms after tripping. It operates within a temperature range of -40°C to +85°C and utilizes a bulk package with a 23.11 mm diameter.

Ptc Resettable Fuses Feature Summary

• Provides reliable overcurrent protection for circuits, wiring harnesses, and PCB components through polymer heating mechanisms.
• Offers automatic reset functionality upon cooling, eliminating the need for manual replacement after fault events.
• Supports multiple international safety agency approvals including UL, CSA, TUV, and CQC for global compliance.

Ptc Resettable Fuses Applications

• Protection for automotive actuators, screens, and small motors in commercial and passenger vehicles.
• Overcurrent safeguarding for telephony and networking equipment against high-voltage fault currents.
• Circuit protection for power supply applications requiring radial leaded form factors.

Ptc Resettable Fuses Procurement Notes

Verify the specific packaging configuration required for production, as the RXEF300K is available in both bulk and tape-and-reel formats. Confirm that the 72 V maximum voltage rating aligns with the system's operational requirements. Ensure the 3 A hold current meets the circuit's continuous load demands without nuisance tripping during normal operation.

Ptc Resettable Fuses Selection Notes

Select this component when a radial leaded PPTC device is necessary for 72 V systems requiring 3 A continuous protection. Consider the 40 A maximum fault current capability for short-circuit scenarios. Evaluate the 100 mOhms maximum resistance to ensure it does not cause excessive voltage drop in low-voltage signal paths.

Ptc Resettable Fuses Part Context

The RXEF300K belongs to the Littelfuse PolySwitch RXEF series, which specializes in radial leaded resettable fuses. This series provides solid-state protection solutions that raise resistance upon heating to limit current flow. The radial leaded format facilitates through-hole mounting on printed circuit boards for robust mechanical connections.

Ptc Resettable Fuses Replacement Considerations

The RXEF300K-2 serves as a verified alternative variant within the same series, offering identical electrical specifications but supplied in tape-and-reel packaging for automated assembly processes. Verify that the footprint and lead spacing remain compatible with existing board layouts.