Equivalent & Substitute Parts: 3FS-228

Part Overview

The 3FS-228 is a laminated core power transformer manufactured by Tamura, rated at 1.1VA with a single primary winding and dual secondary windings. The transformer operates at 115V primary input with configurable secondary outputs of 14V parallel or 28V series, delivering maximum output currents of 80mA parallel or 40mA series respectively. This through-hole mounted component is designed for PC pin termination and maintains 2500Vrms isolation voltage. The part is currently in active production status with RoHS compliance and MSL Level 1 rating. Equivalent substitute parts are identified to provide alternative sourcing options when the primary part is unavailable or when inventory requirements necessitate alternative manufacturer selection.

Substiute Parts

3FS-228

TamuraIn Stock: 9163FS-228 Datasheet

Current PartRFQ

ST-2-28

Signal TransformerIn Stock: 1281ST-2-28 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3FS-228 is determined by strict equivalence across the following critical parameters:

Electrical Specifications:

• Primary voltage: 115V
• Secondary voltage configuration: Parallel 14V / Series 28V
• Maximum output current: Parallel 80mA / Series 40mA
• Power rating: 1.1VA
• Isolation voltage: 2500Vrms
• Winding configuration: Single primary, dual secondary, no center tap

Mechanical Specifications:

• Core type: Laminated
• Mounting type: Through hole
• Termination style: PC pin

Compliance Requirements:

• RoHS compliance status
• ECCN classification: EAR99
• HTSUS code: 8504.31.4035

Substitute parts must match all electrical specifications and mounting characteristics. Dimensional variations within manufacturing tolerances are acceptable provided the component maintains through-hole mounting compatibility and PC pin termination.

Parameter Comparison

Engineering Selection Recommendations

The ST-2-28 manufactured by Signal Transformer qualifies as a direct electrical equivalent to the 3FS-228. Both components share identical electrical specifications across all critical parameters: 1.1VA power rating, 115V primary input, dual secondary windings with 14V parallel and 28V series configurations, and 2500Vrms isolation voltage.

Both parts maintain active product status and comply with RoHS requirements. The ST-2-28 carries ROHS3 compliance certification, which represents an enhanced RoHS standard. Both components are classified under identical ECCN (EAR99) and HTSUS (8504.31.4035) codes.

Dimensional differences between the two parts are minor: the ST-2-28 measures 34.90mm length and 28.60mm width compared to the 3FS-228 at 35.56mm length and 31.00mm width. Height seated maximum is 24.60mm for the ST-2-28 versus 25.40mm for the 3FS-228. These dimensional variations remain within acceptable manufacturing tolerances for through-hole mounted transformers and do not affect functional compatibility or PCB layout considerations for standard applications.

Selection between these parts should be based on availability, packaging format (Tamura supplies in tube packaging; Signal Transformer supplies in box packaging), and inventory requirements rather than technical performance differences.

Frequently Asked Questions (FAQ)

Q: Can the ST-2-28 be used as a direct replacement for the 3FS-228 in existing designs?

A: Yes. The ST-2-28 is electrically equivalent to the 3FS-228 across all specified parameters. Both components provide identical primary voltage input, secondary voltage outputs, current ratings, isolation voltage, and power handling capacity. Through-hole mounting and PC pin termination are identical on both parts.

Q: What are the dimensional differences between these two transformers?

A: The ST-2-28 is slightly smaller than the 3FS-228. Length differs by 0.66mm (34.90mm vs 35.56mm), width differs by 2.40mm (28.60mm vs 31.00mm), and height differs by 0.80mm (24.60mm vs 25.40mm). These differences are within standard manufacturing tolerances for laminated core transformers and do not affect PCB mounting compatibility for applications designed for through-hole transformer installation.

Q: Are there compliance differences between the 3FS-228 and ST-2-28?

A: Both parts are RoHS compliant. The ST-2-28 carries ROHS3 certification, which represents current RoHS standards. Both components share identical ECCN (EAR99) and HTSUS (8504.31.4035) classifications. The 3FS-228 carries MSL Level 1 rating (unlimited moisture sensitivity level), while the ST-2-28 lists moisture sensitivity as not applicable.

Q: What is the difference in packaging between these two parts?

A: The 3FS-228 is supplied in tube packaging, while the ST-2-28 is supplied in box packaging. This distinction affects handling, storage, and bulk ordering considerations but does not impact component functionality or electrical performance.

Q: Are both parts currently in active production?

A: Yes. Both the 3FS-228 and ST-2-28 maintain active product status with manufacturers. The 3FS-228 has 880 pieces in current inventory stock, while the ST-2-28 has 1207 pieces in current inventory stock.

Q: What electrical parameters must match for transformer substitution?

A: Critical matching parameters include primary voltage (115V), secondary voltage configuration (14V parallel / 28V series), output current ratings (80mA parallel / 40mA series), power rating (1.1VA), isolation voltage (2500Vrms), winding configuration (single primary, dual secondary, no center tap), and core type (laminated). All these parameters are identical between the 3FS-228 and ST-2-28.