Comprehensive Industry Knowledge: ED-Core Magnetic Cores
1. ED-Core Overview
ED-Core (ED-Type Magnetic Core) is a high-performance split magnetic component manufactured from grain-oriented silicon steel strips. It consists of two identical "E-like" half-cores, forming a closed magnetic circuit when paired. The "ED" designation refers to its characteristic double-rectangular profile.
Designed for low core loss, high magnetic permeability, and flexible assembly, ED-Cores are widely used in transformers, inductors, power supplies, and audio equipment. Their split design allows for precise air gap adjustment, making them ideal for applications requiring stable inductance and resistance to magnetic saturation.
2. Translated Technical Parameters (From Product Brochure)
| Core Model | Dimensions (mm) a × b × c × h | Output Power (VA) 50Hz / 400Hz | Core Weight (kg) |
|---|---|---|---|
| ED6×6.5 | 6 × 6.5 × 6 × 15 | -- / 7.54 | 0.016 |
| ED6×8 | 6 × 8 × 6 × 15 | -- / 9.54 | 0.017 |
| ED6×10 | 6 × 10 × 6 × 15 | -- / 12.20 | 0.024 |
| ED6×12.5 | 6 × 12.5 × 6 × 15 | -- / 15.40 | 0.030 |
| ED8×8 | 8 × 8 × 8 × 20 | -- / 19.00 | 0.034 |
| ED8×10 | 8 × 10 × 8 × 20 | -- / 23.80 | 0.043 |
| ED8×12.5 | 8 × 12.5 × 8 × 20 | -- / 29.20 | 0.056 |
| ED8×16 | 8 × 16 × 8 × 20 | -- / 36.30 | 0.070 |
| ED10×10 | 10 × 10 × 10 × 25 | 1.60 / 40.70 | 0.070 |
| ED10×12.5 | 10 × 12.5 × 10 × 25 | 2.33 / 49.30 | 0.090 |
| ED10×16 | 10 × 16 × 10 × 25 | 3.51 / 60.70 | 0.110 |
| ED10×20 | 10 × 20 × 10 × 25 | 4.92 / 72.20 | 0.140 |
| ED12×12.5 | 12 × 12.5 × 12 × 30 | 5.01 / 69.30 | 0.150 |
| ED12×16 | 12 × 16 × 12 × 30 | 7.53 / 83.30 | 0.170 |
| ED12×20 | 12 × 20 × 12 × 30 | 10.70 / 98.10 | 0.200 |
| ED12×25 | 12 × 25 × 12 × 30 | 15.10 / 113.00 | 0.250 |
| ED16×16 | 16 × 16 × 16 × 40 | 23.70 / 184.60 | 0.280 |
| ED16×20 | 16 × 20 × 16 × 40 | 33.60 / 214.70 | 0.370 |
| ED16×25 | 16 × 25 × 16 × 40 | 42.90 / 248.50 | 0.450 |
| ED16×32 | 16 × 32 × 16 × 40 | 57.10 / 293.00 | 0.580 |
| ED20×20 | 20 × 20 × 20 × 50 | 62.00 / 327.00 | 0.550 |
| ED20×25 | 20 × 25 × 20 × 50 | 80.00 / 378.00 | 0.700 |
| ED20×32 | 20 × 32 × 20 × 50 | 104.00 / 445.00 | 0.800 |
| ED20×40 | 20 × 40 × 20 × 50 | 132.00 / 516.00 | 1.100 |
| ED25×25 | 25 × 25 × 25 × 63 | 141.00 / 614.00 | 1.050 |
| ED25×32 | 25 × 32 × 25 × 63 | 183.00 / 722.00 | 1.350 |
| ED25×40 | 25 × 40 × 25 × 63 | 230.00 / 836.00 | 1.680 |
| ED25×50 | 25 × 50 × 25 × 63 | 287.00 / 969.00 | 2.100 |
| ED32×32 | 32 × 32 × 32 × 80 | 337.00 / 1262.00 | 2.200 |
| ED32×40 | 32 × 40 × 32 × 80 | 422.00 / 1461.00 | 2.800 |
| ED32×50 | 32 × 50 × 32 × 80 | 522.00 / 1688.00 | 3.450 |
| ED32×64 | 32 × 64 × 32 × 80 | 662.00 / 1984.00 | 4.400 |
| ED40×40 | 40 × 40 × 40 × 100 | 737.00 / 2408.00 | 4.300 |
| ED40×50 | 40 × 50 × 40 × 100 | 914.00 / 2795.00 | 5.320 |
| ED40×64 | 40 × 64 × 40 × 100 | 1154.00 / 3291.00 | 6.900 |
| ED40×80 | 40 × 80 × 40 × 100 | 1408.00 / 3805.00 | 8.600 |
3. Production Process of ED-Cores
The manufacturing of ED-Cores demands high precision and strict quality control to ensure optimal magnetic performance:
Raw Material Selection: Premium grain-oriented silicon steel strips (0.23–0.35mm thickness) are chosen for their low core loss and high permeability.
Slitting & Cutting: Strips are precision-slit to the required width and cut to length, with dimensional tolerances held to ±0.05mm.
Winding & Forming: The cut strips are tightly wound into two identical half-core profiles using automated winding machines, ensuring uniform stacking and minimal internal gaps.
Annealing: The wound cores undergo high-temperature annealing in a nitrogen atmosphere to relieve internal stress and enhance magnetic properties.
Insulation Coating: A high-temperature insulating varnish is applied to prevent inter-lamination short circuits and improve corrosion resistance.
Assembly & Testing: The two half-cores are aligned and paired, with air gaps adjusted to specifications. Each core is tested for inductance, core loss, and saturation characteristics.
Final Inspection: Visual, dimensional, and electrical checks confirm compliance with standards before packaging.
4. Packaging & Transportation
Packaging
Inner Protection: Each core is individually wrapped in anti-static bubble wrap or foam to prevent scratches and impact damage.
Outer Packaging: Sturdy corrugated cartons with foam dividers hold cores in place, clearly labeled with model, quantity, and handling instructions.
Moisture Control: Desiccant packets are included to prevent oxidation, especially for sea freight shipments.
Customization: OEM/ODM packaging with customer logos and barcodes is available upon request.
Transportation
Shipping Options:
Air freight for urgent orders (small/medium cores).
Sea freight for bulk shipments (cost-effective, 20–45 day lead times).
Courier services (DHL/FedEx) for samples or small batches.
Handling Notes: Avoid dropping or stacking heavy loads. Store in a dry, temperature-controlled environment (15–30°C) away from strong magnetic fields.
5. Advantages & Disadvantages of ED-Cores
✅ Advantages
Low Core Loss: Oriented silicon steel construction minimizes energy loss, improving transformer efficiency.
Adjustable Air Gaps: The split design allows precise air gap tuning to reduce saturation and stabilize inductance.
Compact Size: High permeability enables smaller core footprints compared to traditional EI-cores for the same power rating.
Flexible Assembly: Modular half-cores simplify winding and assembly, reducing production time and costs.
Broad Compatibility: Suitable for audio transformers, power inductors, UPS systems, and high-frequency power supplies.
❌ Disadvantages
Higher Cost: Premium materials and precision manufacturing make ED-Cores more expensive than conventional EI-cores.
Alignment Sensitivity: Misalignment of the two half-cores can introduce unwanted air gaps, degrading performance.
Mechanical Fragility: Thin laminations are prone to damage if mishandled during assembly or transport.
Over-Engineering for Low-End Use: The cost and precision benefits are less impactful for low-cost, low-efficiency applications.
6. Frequently Asked Questions (FAQ)
Q1: What are the primary applications of ED-Cores?
A: ED-Cores are used in audio transformers, high-frequency inductors, UPS systems, inverters, medical power supplies, and communication base station equipment. They excel in applications requiring high efficiency and stable performance.
Q2: How do I select the right ED-Core model?
A: Choose based on three key factors:
Rated power (VA) and operating frequency (50Hz/400Hz or higher).
Physical dimensions (a × b × c × h) to fit your device's form factor.
Core weight and loss characteristics for efficiency requirements. Contact our engineering team for custom recommendations.
Q3: Can ED-Cores be customized?
A: Yes. We offer custom ED-Cores with tailored dimensions, air gaps, and coatings to meet unique application needs. Custom orders typically take 4–6 weeks for production.
Q4: What is the typical lead time for standard ED-Cores?
A: Standard models have a 2–3 week lead time, depending on order quantity and availability.
Q5: How should I store ED-Cores to prevent degradation?
A: Store cores in a dry, temperature-controlled environment (15–30°C) away from moisture and strong magnetic fields. Avoid prolonged storage exceeding 24 months to prevent oxidation.