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EI Transformer Core-689
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EI Transformer Core

GNEE EC can provide premium-value ei transformer cores for your magnetic core projects, offering excellent magnetic efficiency, minimal energy losses, easy installation, and wide adaptability. They are widely used in many applications, including ei transformers, sensors, voltage regulators, computer power supplies, leakage protection switches, welding machines, magnetic amplifiers, reactors, and the instrumentation industries.

Focusing on transformer core development for over 18 years, Gnee has grown into a leading transformer core supplier in China. Nowadays, we have equipped with several sets of longitudinal shearing equipment, annealing equipment, and more than one hundred sets of molds. It produces more than 10,000 tons of 0.35, 0.5mm ei transformer cores annually, up to both GB standards and international standards. Besides, our technical capabilities & expertise also have earned us accreditations for ISO 9001, trusted by many global customers for repeated purchases.

Our ei transformer cores now are available in a wide range of materials (CRGO/CRNGO), sizes, phases (single/three), coatings (T2/T4), packaging methods, etc. Also support customization design, feel free to contact us immediately to discuss your specific requirements for the next project plan.

Tel/WhatsApp: +86 19949147586

Common EI Transformer Core Specifications From GNEE EC

EI Transformer Core Specifications (Single-phase Series)

Single-phase EI Transformer Core Specifications

Model A B C D E F G Hole
El-28 28 21 8 4 6 17 4
EI-30 30 20 10 5 5 15 5
El-35 35 24.5 10 5 7.5 19.5 5
EI-38.4 38.4 25.6 12.8 6.4 6.4 19.2 6.4
EI-38.4 38.4 44.8 12.8 6.4 6.4 38.4 6.4
EI-41 41 27 13 6 8 21 6 3.2
E1-42 42 28 14 7 7 21 7 3.5
E1-48 48 32 16 8 8 24 8 3.5
EI-50 50 34 14 9 9 25 8
E1-54 54 36 18 9 9 27 9 3.5
E1-57 57 38 19 9.5 9.5 28.5 9.5 4.0
EI-60 60 40 20 10 10 30 10 3.5
E1-66 66 44 22 11 11 33 11 4.5
EI-75 75 50 25 12.5 12.5 37.5 12.5
EI-76.2 76.2 50.8 25.4 12.7 12.7 38.1 12.7 5.0
E1-78 78 52 26 13 13 39 5 13.0
E1-78 78 53 22 14 14 39 14 5.0
E1-84 84 56 28 14 14 42 5 14.0
El-85.8 85.8 57.2 28.6 14.3 14.3 42.9 14.3 5.0
E1-96 96 64 32 16 16 48 16 6.2
EI-105 105 70 35 17.5 17.5 52.5 17.5 6.0
EI-108 108 72 36 18 18 54 18 5.5
El-114 114 76 38 19 19 57 19 7.0
El-120 120 80 40 20 20 60 20 7.0
El-126 126 84 42 21 21 63 21 14.0
El-132 132 88 44 22 22 66 22 7.0
El-133.2 133.2 88.8 44.4 22.2 22.2 66.6 22.2 7.0
EI-144 144 98 40 26 26 72 26 7.0

EI Transformer Core Specifications (Three-phase Series)

EI Transformer Core Specifications (Three-phase Series)

Model A B C D E Hole
Quantity
3PEI-16 80 16 48 16 16 4 5
3PEI-20 100 20 60 20 20 6 4.5
3PE-22 110 22 66 22 22 4 8
3PEI-25 125 25 75 25 25 6 4.5
3PEI-30 150 30 90 30 30 4 8
3PEI-32 160 32 80 32 32 4 8
3PEI-35 175 35 105 35 35 4 8
3PEI-38 190 38 114 38 38 4 8
3PEI-40 200 40 120 40 40 6 8
3PEI-44 220 44 132 44 44 6 8
3PEI-45 225 45 135 45 45 4 8
3PEI-50 250 50 150 50 50 6 8

*Notice:

Material: High-grade silicon steel laminations

Temperature Range: Designed to operate efficiently at a wide range of temperatures

Customization: Support customizable lamination thickness to suit specific frequency requirements

What Is EI Transformer Core?

EI transformer core is a type of magnetic iron core widely used in transformers, inductors, and other electromagnetic devices due to its excellent magnetic properties and compact design.
The name “EI” comes from the shape of the core, which consists of two parts: an “E” section and an “I” section. The “E” shape forms the central leg of the core, which is where the primary and secondary windings are placed. The three arms of the “E” laminaiton provide a path for the magnetic flux generated by the alternating current in the windings. The “I” shape complements the “E” shape, serving as the return path for the magnetic flux. The I-lamination is placed adjacent to the E-lamination, creating a closed magnetic circuit that enhances the efficiency of the electrical equipment.

What Types of EI Transformer Cores Can GNEE EC Supply?

With our powerful production capability and advanced R&D experience, Gnee can produce ei lamination cores for transformers in many standards.

1. According to Material:

At GNEE EC, 90% of our ei transformer cores are primarily made from silicon steel sheets, which is hot-rolled or cold-rolled and coated with insulating coatings to reduce eddy current losses. The thickness of silicon steel sheets is generally between 0.25 mm and 0.5 mm, with common thicknesses of 0.35 mm and 0.5 mm. According to the grain orientation, it can be further divided into:

CRGO EI Transformer Core: made from grain oriented silicon steel. The magnetic permeability is very high along the rolling direction and the loss is low, which is used for high-efficiency transformers.

CRNGO EI Transformer Core: made from non grain oriented silicon steel. It has isotropic properties with low cost, very suitable for ordinary transformers.

2. According to Phase Number:

Single-phase EI Transformer Core: usually composed of E-shaped and I-shaped silicon steel sheets stacked alternately to form a compact core structure, which is suitable for single-phase transformers.

Three-phase EI Transformer Core: adopts a three-phase symmetrical design, usually a combination of three groups of E-I laminations, with uniform magnetic flux distribution and a more complex structure, which is suitable for three-phase transformers.

3. According to Size:

Small EI Transformer Core: EI-28, EI-35 (used for low-power adapters, chargers, etc.).

Medium EI Transformer Core: EI-48, EI-54 (commonly used in audio transformers, household appliance power supplies).

Large EI Transformer Core: EI-76, EI-114 (industrial transformers, high-power power supplies).

EI Transformer Core Manufacturing Process

What Are the Advantages of EI Transformer Cores Offered by GNEE EC?

1. High Magnetic Efficiency: The design of the core provides effective magnetic coupling between the windings, which allows for efficient energy transfer during operation.

2. Reduced Core Loss: High-quality silicon steel material reduces energy losses, contributing to lower electricity bills and improved overall system performance.

3. Simple Geometric Structure: The core has a simple shape configuration — E and I, which not only simplifies the manufacturing process but also allows for easy assembly.

4. Long Lifespan: Built with durable materials, our transformer ei cores offer a long operational lifespan of over 20 years, ensuring a long lifespan and reduced maintenance costs.

5. Affordable & Economical: The design and manufacturing of EI transformer core laminations are relatively straightforward, often resulting in lower costs compared to other transformer core types.

What Are the Main Applications of Gnee’s Transformer EI Cores?

Transformer ei cores are widely used in various industries, including:

1. Transformer Manufacturing: Widely used in the design and manufacturing of various transformers, including EI transformers, distribution transformers, etc.

2. Industrial Equipment: Helps to handle high magnetic flux densities and low core losses in industrial equipment, ensuring efficient and reliable operation.

3. Home Appliances: Found in many household appliances such as microwave ovens, refrigerators, and heating systems.

4. Switching Power Supplies: Commonly found in power supply applications for electronic devices, helping manage voltage conversion efficiently.

5. Inductive Components: Also found in inductive components, such as chokes and filters, where efficient magnetic coupling is necessary.

EI Transformer Core Applications

Why Choose GNEE EI Transformer Cores?

As a world-leading manufacturer and supplier of transformer cores, GNEE EC has accumulated 18 years of professional experience and grown to be an industry expert. We have built 5 production bases, introduced 30 sets of advanced production equipment, and equipped with 200 technicians, achieving an annual production capacity of 10 million tons. Our transformer cores are well exported to more than 50 countries, widely used in different electrical projects, covering more than 1000 transformer solutions. With strict quality control and professional technical support, more than 90% of our customers maintain long-term cooperation with us, and customer satisfaction continues to remain above 95%. Choose Gnee, you can obtain:

Superior Material Quality

Our transformer cores are crafted using premium silicon steel and other high-grade materials (like ferrities and amorphous metal for high-frequency applications), ensuring minimal energy loss and enhanced efficiency in power transmission.

Precision Manufacturing

We utilize advanced manufacturing techniques and automatic production processes to guarantee precise dimensions, small burrs, good flatness, and optimal performance. We gugarantee: lamination coefficient ≥96%, burr control ≤0.02mm, and air gap < 0.1%.

Production

Complete Quality Assurance System

Quality is a core value at GNEE EC. We possess 8 international certifications including ISO9001. More than that, we conduct factory acceptance testing (FAT), type testing, and third-party inspection tests to ensure excellence. The scope of the test includes:

Transformer Core Material Performance Test

Transformer Core Grounding Fault Test

Transformer Core Mechanical & Appearance Inspection

Insulation Performance Test

Electrical Performance Test

Strict Quality Control

Rich Successful Cooperation Cases

So far, we have established partnerships with electrical companies in more than 50 countries, providing over 1000+ global magnetic core solutions. What we are most proud of is that the longest cooperation period is over 17 years. You can trust Gnee’s strength in offering you the best project guidance plan.

Adequate Inventory Guarantee

Our factory guarantees strong production capacity. More than 30 sets of automatic machines can be put into more professional and faster iron core production, with a daily input of 320+ tons.

The standing inventory is maintained at more than 3 million sets, which ensures a 48-hour fast delivery service for general goods. Besides, the inventory turnover rate is controlled at 45 days, effectively supporting market demands and customer project plans.

Package & Shippment

Professional Customization Solution

GNEE EC supports impeccable customization services to meet specific application requirements, enabling you to achieve the best performance for your electrical systems. The common customization options include: material, parameter, size, function, insulation, etc., to help your project be successfully realized. Feel free to communicate with us about your project drawings~

Gnee Team

Comprehensive Customer Service

Expert Technical Support: Our team of experienced engineers is able to provide professional consultation and technical assistance, helping you select the right core solution for your application.

Full Pre-sales & After-Sales Service: We provide full service support from pre-sales consultation to after-sales exception handling, fostering long-term relationships built on trust and service.

Customer Visit

No matter where or when it’s needed, the GNEE EC team is ready and available to help you. Transformer cores are what we do best and nothing can stop us from delivering top-tier service and support each time.

No matter your project is large or small, we hope to get your inquiry!


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