Regarding Low-frequency Transformers.
2026-04-09
EI type power frequency transformer adopts a mature all copper wire winding process. Compared with aluminum wire transformers, it has significant advantages in voltage stability and service life under long-term loads, and is particularly suitable for equipment scenarios that require continuous and stable power supply. Its metal shielding shell design can not only effectively suppress electromagnetic radiation interference, but also resist the influence of external clutter on signals, providing a pure power environment for audio equipment and precision instruments.
In terms of safety and reliability, the product has undergone strict withstand voltage testing and aging testing, and the insulation level meets industry standards. At the same time, it has a moisture-proof and vibration proof structural design, which is suitable for different regions' power grid environments and complex working conditions. The installation bracket and terminal design at the bottom significantly reduce the difficulty of customer assembly, support rapid batch installation, and effectively improve customer production efficiency.
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Physical structure
1.EI type silicon steel core: The main body is composed of E-type and I-type silicon steel sheets stacked together, and is wrapped in a metal shielding shell (which not only provides protection, but also shields electromagnetic interference and reduces external radiation).
2.Double winding design:
Primary winding (red wire): With a large number of turns and a thin wire diameter, it is responsible for high-voltage conversion tasks.
Secondary winding (white wire): with fewer turns and thicker wire diameter, responsible for low-voltage output and reducing wire resistance losses.
3.Installation structure: The bottom is equipped with metal mounting feet/brackets for easy fixation on the equipment chassis or circuit board.
4.Connector: Comes with white plastic terminal blocks at the end, making it easy to insert directly into the PCB board for installation without the need for manual wire stripping and welding, improving assembly efficiency.
2.Double winding design:
Primary winding (red wire): With a large number of turns and a thin wire diameter, it is responsible for high-voltage conversion tasks.
Secondary winding (white wire): with fewer turns and thicker wire diameter, responsible for low-voltage output and reducing wire resistance losses.
3.Installation structure: The bottom is equipped with metal mounting feet/brackets for easy fixation on the equipment chassis or circuit board.
4.Connector: Comes with white plastic terminal blocks at the end, making it easy to insert directly into the PCB board for installation without the need for manual wire stripping and welding, improving assembly efficiency.
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Process characteristics
1.Sealing/Insulation: Yellow skeleton+outer tape/sealing glue to ensure insulation between the winding and the iron core, improving voltage resistance and moisture resistance.
2.All copper winding: Judging from the color and texture of the wire, the interior is made of enameled wire winding, which has good conductivity and thermal conductivity.
2.All copper winding: Judging from the color and texture of the wire, the interior is made of enameled wire winding, which has good conductivity and thermal conductivity.
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Working principle and characteristics
1. Working principle
Based on Faraday's law of electromagnetic induction, voltage conversion and electrical isolation are achieved through electromagnetic induction
Primary side: 220V AC power enters the red wire winding, generating an alternating magnetic field in the iron core.
Electromagnetic conversion: The alternating magnetic field is coupled to the secondary winding through silicon steel sheets.
Secondary side: Induced 14.5V low-voltage AC power based on the turns ratio for use in the back-end circuit.
Isolation function: The primary and secondary windings are only coupled by a magnetic field, completely isolated electrically, effectively isolating the impact of high voltage from the mains on the low voltage side circuit and ensuring safety.
2. Core Features
Power frequency operation: specially designed for 50Hz/60Hz power frequency grids, different from high-frequency switching power transformers.
Low loss: The EI structure design is mature, with high magnetic flux utilization, low heat generation, and stable operation.
Strong anti-interference: The metal shell shields external electromagnetic radiation, making it suitable for analog circuits that require high purity power supply (such as audio and power amplifiers).
Based on Faraday's law of electromagnetic induction, voltage conversion and electrical isolation are achieved through electromagnetic induction
Primary side: 220V AC power enters the red wire winding, generating an alternating magnetic field in the iron core.
Electromagnetic conversion: The alternating magnetic field is coupled to the secondary winding through silicon steel sheets.
Secondary side: Induced 14.5V low-voltage AC power based on the turns ratio for use in the back-end circuit.
Isolation function: The primary and secondary windings are only coupled by a magnetic field, completely isolated electrically, effectively isolating the impact of high voltage from the mains on the low voltage side circuit and ensuring safety.
2. Core Features
Power frequency operation: specially designed for 50Hz/60Hz power frequency grids, different from high-frequency switching power transformers.
Low loss: The EI structure design is mature, with high magnetic flux utilization, low heat generation, and stable operation.
Strong anti-interference: The metal shell shields external electromagnetic radiation, making it suitable for analog circuits that require high purity power supply (such as audio and power amplifiers).
- Typical application scenarios
This product is a universal power transformer with a wide range of applications and is also one of the key display products on your foreign trade website:
1.In the field of home appliances: built-in power supplies for audio amplifiers, radios, humidifiers, and air purifiers.
2.Security/office equipment: Low voltage power supply for access controllers, attendance machines, printers, and scanners.
3.Industrial control: auxiliary power supply for industrial automation instruments, sensors, and PLC control cabinets.
4.New energy support: As an auxiliary low-voltage power source (non main power source) for charging stations and on-board equipment.
1.In the field of home appliances: built-in power supplies for audio amplifiers, radios, humidifiers, and air purifiers.
2.Security/office equipment: Low voltage power supply for access controllers, attendance machines, printers, and scanners.
3.Industrial control: auxiliary power supply for industrial automation instruments, sensors, and PLC control cabinets.
4.New energy support: As an auxiliary low-voltage power source (non main power source) for charging stations and on-board equipment.
Definition, Function, and Classification of Power Transformers.
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