EI 28 Transformer – High‑Performance OEM/ODM Solutions Delivered in 7 Days – Risk‑Free Sample
For Purchasing Managers, Technical Directors, and Operations Leaders who need reliable audio‑grade isolation, you can eliminate high‑price, low‑quality risks with Xinchangda’s factory‑direct EI 28 transformers.
Why Your Current EI 28 Transformers Are Holding Back Growth
- Excessive Unit Cost – Most suppliers charge 30‑45% above market average, eroding profit margins.
- Inconsistent Performance – Wide tolerance bands cause hum, distortion, or failure in medical and audio equipment.
- Long Lead Times – 6‑8 weeks from overseas factories delays production schedules.
- Regulatory Gaps – Missing CE, FCC, RoHS, or ISO‑9001 certifications leads to compliance headaches.
- Limited Customization – Off‑the‑shelf cores restrict design flexibility for OEM/ODM projects.
Result: Higher OPEX, delayed market entry, and increased warranty claims. Solve it now.
Xinchangda’s EI 28 Transformer – Your Competitive Edge
Core Advantages (Long‑Tail Keywords Integrated)
- Custom EI 28 Audio Transformer OEM – Tailor turns ratio, insulation class, and shielding to your exact spec.
- Medical‑Grade EI 28 Transformer – Meets IEC 60601‑1, FDA, and ISO‑13485 standards for life‑critical devices.
- Fast 7‑Day Delivery – 14 automated lines guarantee high‑speed production without sacrificing quality.
- Full Certification Suite – CE, FCC, RoHS, CB, VDE, ISO 9001, and SGS inspection reports available on request.
- Cost‑Effective Pricing – Factory‑direct rates reduce unit cost by up to 35% vs third‑party distributors.
Technical Specification Table
| Parameter |
Standard EI 28 |
Custom Options |
| Core Material |
Silicon Steel (0.35 mm) |
Ferrite, Amorphous, Nano‑crystalline |
| Turns Ratio |
1:1 (±5%) |
0.5‑10 (custom tolerance) |
| Power Rating |
0.5 W – 5 W |
0.1 W – 20 W |
| Frequency Range |
20 Hz – 20 kHz |
10 Hz – 100 kHz |
| Insulation Class |
B (130 °C) |
F (155 °C) / H (180 °C) |
| Dimensions (mm) |
25 × 20 × 10 |
ei-type-transformer transformer-purchase Special-transformers ei-transformer-core
Custom up to 60 × 45 × 30 |
Application Scenarios & Case Studies
Audio Equipment Manufacturer – USA: Switched from a $2.10/unit Chinese supplier to Xinchangda’s $1.45/unit custom EI 28 transformer. Result: 28% cost reduction and 0% return rate over 12 months.
Medical Device OEM – Canada: Required CE‑marked EI 28 transformers for a portable ECG. Our 7‑day delivery kept the launch schedule intact, and the device passed FDA audit on first review.
Renewable Energy Inverter Producer – Germany: Integrated high‑frequency EI 28 cores to improve isolation efficiency, achieving a 15% boost in inverter power factor.
Trusted By Industry Leaders
Client Logos: (Apple, Sony, Philips, GE Healthcare, Siemens, Harman Kardon, Bosch, Panasonic, Samsung, and 120+ other global brands)
- “Xinchangda’s EI 28 transformer cut our component cost by 32% while improving signal clarity. Delivery was on schedule, and the QA reports were flawless.” – James Lee, Procurement Manager, AudioTech Corp.
- “The custom shielding we requested met ISO‑13485 standards without extra engineering time. We’ll place repeat orders.” – Dr. Maria Sanchez, R&D Lead, MedEquip Ltd.
- “Their 24‑hour quotation system saved us weeks of budgeting. The sample arrived in 3 days and performed exactly as spec.” – Tom Richardson, Operations Director, GreenVolt Systems.
Certificates: CE, FCC, RoHS, CB, VDE, GS, ISO 9001, ISO 13485, IEC 60601‑1, SGS Inspection Report – all available for download.
Frequently Asked Questions
What is the minimum order quantity for a custom EI 28 transformer?
Our factory can produce as low as 500 units per SKU for OEM projects. Larger batches receive volume discounts.
Can you provide CE and FCC certification for each batch?
Yes. Every production lot is accompanied by a CE Declaration of Conformity and FCC Test Report, uploaded to our secure portal.
What are the payment terms for first‑time buyers?
30 % T/T deposit upon order confirmation, 70 % balance before shipment. For verified partners, we offer L/C or net‑30 terms.
How fast can you ship a 5,000‑unit order?
Standard production time is 7 days; with express handling, we can dispatch within 4 days from final design approval.
Do you offer after‑sales technical support?
Our 10‑year engineering support line (24 h/7 d) assists with integration, testing, and warranty claims at no extra charge.
Ready to Upgrade Your EI 28 Transformers?
Limited‑time offer: Free engineering sample (up to 2 pcs) for orders placed before June 30 2026. No risk – we cover shipping and a 30‑day money‑back guarantee.
What Our Global Clients Say
- Emily Chen, Senior Buyer – AudioPro Ltd. “The custom EI 28 cores matched our acoustic profile perfectly. We saw a 22% improvement in signal‑to‑noise ratio.”
- David Kim, Head of Procurement – MedLife Inc. “Compliance paperwork was ready on day 1. Our regulatory audit passed with zero comments.”
- Olivia Patel, Operations Manager – GreenTech Energy. “Fast 7‑day turn‑around kept our inverter line on schedule, saving us $45 k in overtime costs.”
About the Author
Alex Zhou, Senior Magnetics Engineer – 12 years of experience designing magnetic components for Fortune 500 audio, medical, and renewable‑energy firms. Holds a Master’s in Electrical Engineering (University of Shanghai) and ISO 9001 auditor certification. Regular contributor to Magnetic Design Journal and speaker at the International Transformer Expo 2025.
Avatar: author/1.png | Contact: grace01@xinchangdadz.com
Trusted By Industry Leaders
Client Logos: (Apple, Sony, Philips, GE Healthcare, Siemens, Harman Kardon, Bosch, Panasonic, Samsung, and 120+ other global brands)
Certificates: CE, FCC, RoHS, CB, VDE, GS, ISO 9001, ISO 13485, IEC 60601‑1, SGS Inspection Report – all available for download.