F28-85 Equivalent & Substitute Parts Reference

Part Overview

The F28-85 is a laminated core power transformer manufactured by Triad Magnetics, rated at 2.5VA with through-hole mounting and PC pin termination. This Class 2/3 transformer operates with a single primary winding at 115V and dual secondary windings configured for parallel (14V, 170mA) or series (28V, 85mA) output. The part is currently active in production with ROHS3 compliance and 2500Vrms isolation rating. Substitute parts are identified when inventory constraints, lead time requirements, or design flexibility necessitate alternative sourcing while maintaining electrical and mechanical compatibility.

Substiute Parts

F28-85

Triad MagneticsIn Stock: 1017F28-85 Datasheet

Current PartRFQ

164E28

Hammond ManufacturingIn Stock: 919164E28 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the F28-85 is determined by strict equivalence across the following critical parameters:

Electrical Compatibility Requirements:

• Primary voltage: 115V (single winding configuration)
• Secondary voltage outputs: Parallel 14V and Series 28V (dual winding configuration)
• Maximum output current: Parallel 170mA and Series 85mA
• Isolation voltage: 2500Vrms minimum
• Core type: Laminated

Mechanical Compatibility Requirements:

• Mounting type: Through Hole
• Termination style: PC Pin
• Physical dimensions: Compatible footprint (length and width within tolerance)
• Height seated: Compatible with PCB assembly constraints

Compliance Requirements:

• RoHS3 compliance mandatory
• REACH unaffected status
• Active product status

The substitute part 164E28 (Hammond Manufacturing) meets all electrical and mechanical compatibility criteria. The power rating differential (2.4VA versus 2.5VA) remains within acceptable tolerance for applications designed for the F28-85, as the maximum output currents and voltages are identical across both parallel and series configurations.

Parameter Comparison

Engineering Selection Recommendations

F28-85 (Triad Magnetics): Select this part as the primary choice when Triad Magnetics inventory is available and lead times are acceptable. The part carries active product status with 980 units in stock, ensuring supply continuity. ROHS3 compliance and REACH unaffected status confirm regulatory alignment for current and future applications.

164E28 (Hammond Manufacturing): This substitute is electrically and mechanically equivalent to the F28-85. The 164E28 is suitable for direct replacement in applications where the F28-85 is unavailable or when Hammond Manufacturing sourcing is preferred. With 858 units in stock, the 164E28 provides alternative supply chain access. The 2.4VA rating (versus 2.5VA) does not impact compatibility, as both parts deliver identical maximum output currents and voltages. Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying identical regulatory requirements.

Packaging Consideration: The F28-85 is supplied in Box packaging, while the 164E28 is supplied in Bulk packaging. Procurement and inventory management processes should account for this packaging difference.

Frequently Asked Questions (FAQ)

Q: Can the 164E28 be used as a direct replacement for the F28-85 in existing designs?

A: Yes. The 164E28 is electrically and mechanically equivalent. Both transformers provide identical primary voltage (115V), secondary voltages (14V parallel, 28V series), maximum output currents (170mA parallel, 85mA series), isolation voltage (2500Vrms), mounting type (through hole), and termination style (PC pin). Physical dimensions are equivalent within tolerance. Both parts are ROHS3 compliant and REACH unaffected.

Q: What is the significance of the power rating difference (2.5VA vs. 2.4VA)?

A: The power rating difference is not significant for substitution purposes. Both transformers deliver identical maximum output currents and voltages in both parallel and series configurations. The power rating reflects the transformer's design margin; the actual electrical performance delivered to the load is determined by the voltage and current specifications, which are identical.

Q: Are there any physical footprint differences between the F28-85 and 164E28?

A: Physical dimensions are equivalent. Both transformers measure 34.93mm length and approximately 28.57mm width (F28-85: 28.58mm, 164E28: 28.56mm). Maximum seated heights are equivalent (F28-85: 30.15mm, 164E28: 30.18mm). Both use through-hole mounting with PC pin termination, ensuring compatible PCB assembly.

Q: Do both parts meet the same regulatory requirements?

A: Yes. Both the F28-85 and 164E28 are ROHS3 compliant and REACH unaffected. Both carry active product status and meet the 2500Vrms isolation voltage requirement for Class 2/3 applications.

Q: What is the difference between Box and Bulk packaging?

A: Box packaging (F28-85) typically includes individual unit packaging suitable for smaller order quantities and component traceability. Bulk packaging (164E28) is used for larger quantities and may require internal inventory management for individual unit tracking. Packaging choice does not affect electrical or mechanical performance.

Q: Can these transformers be used in parallel or series configuration interchangeably?

A: Yes. Both transformers feature dual secondary windings with no center tap, allowing configuration as either parallel (14V, 170mA) or series (28V, 85mA). The configuration is determined by winding connection at assembly, not by the transformer model.