PFRX.300 Equivalent & Substitute Parts

Part Overview

The PFRX.300 is a polymeric PTC resettable fuse manufactured by SCHURTER Inc., rated for 60V maximum voltage with 3A hold current. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The PFRX.300 series provides circuit protection through automatic current limiting in through-hole radial disc configuration, suitable for applications requiring resettable overcurrent protection.

Key Parameters

Parameter	Value
Voltage - Max	60V
Current - Hold (Ih) (Max)	3 A
Current - Trip (It)	6 A
Current - Max	40 A
Time to Trip	19.8 s
Resistance - Initial (Ri) (Min)	40 mOhms
Resistance - Post Trip (R1) (Max)	100 mOhms
Operating Temperature	-40°C ~ 85°C
Mounting Type	Through Hole
Package / Case	Radial, Disc
Lead Spacing	0.402" (10.20mm)
Type	Polymeric

Substitute Part Grouping Explanation

Substitute parts for the PFRX.300 are classified into three categories based on electrical and mechanical compatibility:

Direct Substitutes maintain identical electrical specifications: 60V maximum voltage, 3A hold current, 6A trip current, 19.8s time to trip, 40 mOhms initial resistance, and 100 mOhms post-trip resistance. These parts are mechanically compatible with 0.402" (10.20mm) lead spacing and through-hole radial disc mounting. Direct substitutes include 60R300XF (Littelfuse Inc.), PTR060V0300-BK (Eaton - Electronics Division), and PTR060V0300-BK1 (Eaton - Electronics Division).

Similar Parts share the same voltage rating (60V) and mounting configuration but differ in hold current specifications. These include 60R185XMR (1.85A hold current) and 60R375XH (3.75A hold current), suitable only when circuit requirements permit alternative current ratings.

Parametric Equivalents match all critical electrical parameters (60V, 3A hold, 6A trip, 19.8s trip time) with identical resistance characteristics. The 0ZRR0300FF1A (Bel Fuse Inc.) qualifies as a parametric equivalent with AEC-Q200 automotive qualification.

Voltage-Elevated Alternatives such as PFRY.300 (72V rating) provide higher voltage margin but maintain identical current and resistance specifications, applicable only in designs where higher voltage headroom is acceptable.

Parameter Comparison

Part Number	Manufacturer	Voltage - Max	Current - Hold (Ih)	Current - Trip (It)	Time to Trip	Resistance - Initial (Ri)	Resistance - Post Trip (R1)	Lead Spacing	Product Status
PFRX.300	SCHURTER Inc.	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.402" (10.20mm)	Obsolete
60R300XF	Littelfuse Inc.	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.402" (10.20mm)	Active
PTR060V0300-BK	Eaton - Electronics Division	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.394" (10.00mm)	Active
PTR060V0300-BK1	Eaton - Electronics Division	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.394" (10.00mm)	Active
0ZRR0300FF1A	Bel Fuse Inc.	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.402" (10.20mm)	Active
PTR060V0300-TR1	Eaton - Electronics Division	60V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.394" (10.00mm)	Active
PFRY.300	SCHURTER Inc.	72V	3 A	6 A	19.8 s	40 mOhms	100 mOhms	0.402" (10.20mm)	Active
60R185XMR	Littelfuse Inc.	60V	1.85 A	3.7 A	12.6 s	80 mOhms	190 mOhms	0.201" (5.10mm)	Active
60R375XH	Littelfuse Inc.	60V	3.75 A	7.5 A	24 s	30 mOhms	80 mOhms	0.402" (10.20mm)	Active

Engineering Selection Recommendations

Primary Substitutes for Direct Replacement:

The 60R300XF (Littelfuse Inc., POLY-FUSE® series) and 0ZRR0300FF1A (Bel Fuse Inc.) are recommended as primary direct substitutes. Both maintain identical electrical specifications and lead spacing (0.402" / 10.20mm) with the PFRX.300. The 0ZRR0300FF1A carries AEC-Q200 automotive qualification and cURus/TUV/UL approvals, providing enhanced compliance documentation. Both parts are in active production status with established supply availability.

Secondary Substitutes with Minor Mechanical Variation:

The PTR060V0300-BK, PTR060V0300-BK1, and PTR060V0300-TR1 (Eaton - Electronics Division, PTR060V series) provide electrical equivalence with lead spacing of 0.394" (10.00mm), a 0.008" (0.20mm) reduction from the original specification. These parts are suitable for applications where PCB pad spacing accommodates this tolerance variation. All three are in active production with cURus/TUV approvals.

Voltage-Elevated Alternative:

The PFRY.300 (SCHURTER Inc., 72V rating) maintains identical current and resistance characteristics while providing 12V additional voltage margin. This part is applicable only in designs where the higher voltage rating does not conflict with component derating requirements or circuit topology constraints.

Current-Variant Options:

The 60R185XMR (1.85A hold current) and 60R375XH (3.75A hold current) are suitable only when circuit protection requirements permit deviation from the original 3A specification. The 60R185XMR features reduced lead spacing (0.201" / 5.10mm), requiring PCB redesign. The 60R375XH maintains 0.402" (10.20mm) lead spacing but introduces different resistance and trip time characteristics.

Frequently Asked Questions (FAQ)

Q: Can I use PTR060V0300-BK as a direct replacement for PFRX.300?

A: Yes, with mechanical consideration. The PTR060V0300-BK provides identical electrical specifications (60V, 3A hold, 6A trip, 19.8s trip time, 40 mOhms initial resistance, 100 mOhms post-trip resistance). The lead spacing differs by 0.008" (0.20mm): 0.394" versus the original 0.402". Verify PCB pad spacing tolerances before implementation.

Q: What is the difference between direct substitutes and similar parts?

A: Direct substitutes maintain all electrical parameters and lead spacing identical to the PFRX.300. Similar parts such as 60R185XMR and 60R375XH alter the hold current rating, trip current, or resistance characteristics. Similar parts require circuit analysis to confirm compatibility with the original design intent.

Q: Is the 0ZRR0300FF1A suitable for automotive applications?

A: The 0ZRR0300FF1A carries AEC-Q200 qualification, indicating suitability for automotive environments. It maintains identical electrical specifications to the PFRX.300 with lead spacing of 0.402" (10.20mm) and holds cURus, TUV, and UL approvals.

Q: Why does PFRY.300 have a higher voltage rating?

A: The PFRY.300 is rated for 72V maximum voltage compared to the PFRX.300's 60V rating. This provides 12V additional voltage margin. The PFRY.300 maintains identical current (3A hold, 6A trip) and resistance specifications. Use this part only if circuit design permits the higher voltage rating without affecting component derating calculations.

Q: Can I substitute 60R375XH for PFRX.300?

A: The 60R375XH is not a direct substitute. While both are rated 60V with 0.402" (10.20mm) lead spacing, the 60R375XH has a 3.75A hold current versus the original 3A specification. This results in different trip current (7.5A versus 6A), trip time (24s versus 19.8s), and resistance values. Use only if circuit protection requirements accommodate the higher current rating.

Q: What packaging options are available for direct substitutes?

A: The 60R300XF is available in Bulk packaging. The PTR060V0300-BK and PTR060V0300-BK1 are supplied in Bulk. The PTR060V0300-TR1 is available in Tape & Reel (TR) format for automated assembly. The 0ZRR0300FF1A is supplied in Bulk packaging. Select packaging based on assembly process requirements and order quantity.

Q: Are all substitute parts RoHS compliant?

A: Yes. The PFRX.300 and all listed substitute parts carry ROHS3 Compliant or RoHS Compliant status. All parts are REACH Unaffected with EAR99 ECCN classification and HTSUS code 8533.40.8070.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message