What is the delivery time?

Standard/small orders: 10-15 working days. New customizations require an additional 5-7 days for samples. Large orders: 15-30 days. Raw material price fluctuations may affect timing.

Can samples be provided and how are they charged?

Samples are supported for serious customers. A sample fee is usually required but can be refunded or deducted after placing a bulk order. Sample lead time is typically 3-5 days.

What causes transformer failure and is there a warranty?

Common causes include overload, short circuits, and harsh environments. We provide a 1-year warranty, offering free repair or replacement for product quality issues.

Ei41 Ei28 Ei57 Audio PCB Mounted Encapsulated Electronic Power Transformer

Name: Ei41 Ei28 Ei57 Audio PCB Mounted Encapsulated Electronic Power Transformer
Brand: Hangzhou Udwells Technology Co., Ltd.
SKU: 2229784815

Zhejiang, ChinaHangzhou Udwells Technology Co., Ltd.

US$0.50-1.50

500 Pieces

Product profile

Customization

Available

Application

Power, Electronic, Instrument, Lighting, Rectifier, Audio

Phase

Single

Model NO.

Core

Core-type Transformer

Cooling Method

Dry-type Transformer

Winding Type

Multi-winding Transformer

Certification

ISO9001

Usage

Single-phase Transformer

Frequency Characteristics

Low Frequency

Shape of Core

Operating Temperature

-40ºCTO +125ºC

Storage Temperature

-25ºCTO+85ºC

Customize

Yes

Type

Ei/Toroidal

Installation Method

Vertical/Horizontal/with a Base/with a Cover

Transport Package

Export Standard Carton and Strong Pallet

Specification

EI Series Low Frequency Transformer

Origin

Zhejiang

Production Capacity

200000 PCS/Month

Key features

Customizable Design: Offers full customization including type (EI/Toroidal), installation, and operating temperatures.

High-Quality Materials: Uses new high-grade silicon steel sheets (H18/H14) and 100% pure copper wire.

EMI Shielding Option: Optional copper foil shielding layer effectively suppresses electromagnetic interference.

100% Factory Testing: Every unit undergoes Hi-Pot, inter-winding, and load tests before shipment.

Versatile Applications: Suitable for power, audio, lighting, instruments, and rectifier applications.

Flexible OEM/ODM: Supports OEM/ODM services with flexible customization from samples or designs.

1-Year Warranty: Provides a 1-year warranty covering free repair or replacement for quality issues.

Company profile

High Repeat Buyers ChoiceFast DeliveryPrivate MoldQuality Assurance

Hangzhou Udwells Technology Co., Ltd.

Zhejiang, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: ODM Service Available & OEM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 3 Years CertifiedNearest Port: Shanghai Port, Ningbo PortAverage Response Time: ≤4.34h

AI-Powered supplier vetting

SummaryHANGZHOU UDWELLS TECHNOLOGY CO. Ltd. was founded in 2008 and reports a self-built plant exceeding 15,000 square meters, more than 10 production lines, Europe as a primary export market, and peak-season order fulfillment within 15 working days. It provides multiple customization options, ODM services, and has launched new products within the past year. The supplier also reports OEM service for well-known brands and quality assurance in its quality-control processes. However, no R&D audit documentation, SDK, approved-supplier list, written service procedures, corrective/preventive-action procedures, or complaint-handling procedures were available. Overseas warehouses, showrooms, agents or branches, and offline trade-show participation were not reported. Financial information is insufficient for a credibility judgment, and sustainability-related fire-drill and environmental-assessment status is unknown.

After-Sales capabilityTechnology engineers are responsible for technical support during production and after-sales service, but the supplier has no written procedures or records for effective service assessment, corrective and preventive actions, or customer complaint handling. It also has no overseas warehouse, showroom, agent, or branch, limiting evidence of structured or localized after-sales support.

R&D capabilityThe supplier reports new products within the past year, ODM capability, customization-related R&D services, and use of PS and CAD. It also reports OEM service for well-known brands. Countervailing evidence includes only one year of total R&D engineer experience, no available SDK, and no R&D design-input, output, review, verification, or validation documents for audit.

Production capacityThe supplier reports a self-built plant exceeding 15,000 square meters, more than 10 production lines, complete testing facilities, and peak-season order fulfillment within 15 working days. These explicit operating-scale and delivery statements support a production-capability advantage, although the number of quality-control staff is listed as unavailable.

Customization capabilityThe supplier explicitly offers customization from samples, customization from designs, full customization, flexible customization, and minor customization. It also provides ODM services, demonstrating broad stated customization coverage.

Client casesThe supplier states that it provides OEM services for well-known brands and identifies Europe as a primary export market. These statements indicate some brand and export experience, but no customer names, project details, order references, or verifiable case documentation are provided.

Product Q&A

Q:What specifications are needed for a 220V to 12V transformer?

Please provide input voltage with fluctuation range, output voltage/current, rated power (VA/W), frequency (50Hz/60Hz), construction type (Toroidal/EI/R-type), installation method, and insulation class.

Q:What is the difference between Toroidal and EI transformers?

Toroidal transformers offer higher efficiency, less leakage magnetism, and are ideal for high-end audio/instruments but are costlier. EI transformers are smaller, lighter, cheaper, and suitable for general industrial equipment.

Q:What is the purpose of a shielding layer in a transformer?

A shielding layer (usually copper foil) between primary and secondary coils is grounded to suppress high interference, enhancing EMI resistance, which is essential for audio equipment and measuring instruments.

Q:How do you ensure quality and service life?

We use high-grade silicon steel and pure copper, apply VPI process for insulation, and conduct 100% testing including Hi-Pot, inter-winding, and load tests before leaving the factory.

Q:What is the MOQ and pricing structure?

Price and MOQ depend on specifications. Standard specs may have MOQ of 100pcs; fully custom specs may require 500-1000pcs due to mold opening. Higher quantity lowers unit price.