The toroidal transformer we may have seen, but the toroidal transformer hand-wound method many people do not know, usually need to use the toroidal transformer are purchased, very few people will personally winding the toroidal transformer, this article will explain the method of winding the toroidal transformer, teach you how to wind the transformer, watch the seconds to become a toroidal transformer maker, after mastering this skill, daily life after the transformer is bad! The electrical problems can be repaired on their own, no longer need to ask for help.
Most of the household amplifiers are powered by toroidal transformers. The toroidal transformer has a small magnetic leakage, high conversion efficiency, wide frequency response and other characteristics, which can improve the sound quality of the amplifier. If the toroidal transformer burned out, and can not buy the original model to replace, then only to take the hand-wound method to copy. The following is a description of the hand-wound method.
Ring transformer simple Introduction:
Ring transformer is a large type of electronic transformer, has been widely used in home appliances and other technical requirements of the electronic equipment, its main purpose is to serve as a power transformer and isolation transformer. Toroidal transformer in foreign countries has a complete series, widely used in computers, medical equipment, telecommunications, instruments and lighting, etc.? China in the past decade toroidal transformer from scratch, so far has formed a considerable production scale, in addition to meet domestic demand, but also a large number of exports. Domestic mainly used for home appliances audio equipment and automatic control equipment and quartz lamp lighting, etc.? Toroidal transformer due to excellent performance-price ratio, good output characteristics and anti-interference ability, and therefore it is a competitive electronic transformer, this paper intends to make a presentation on its characteristics.
Product Features
High efficiency core without air gap, stacking factor can be as high as 95% or more.
Lower vibration noise core without air gap can reduce the noise of the core induction vibration, winding uniform tightly wrapped around the annular core, effectively reducing the magnetostriction caused by the "hum" sound.
Low operating temperature due to iron loss can be done 1.1W/kg, iron loss is very small, low temperature rise of the core, the windings in the lower temperature of the core on the heat dissipation situation is good, so the transformer temperature rise is low.
Easy to install toroidal transformers have only one mounting screw in the center, which makes it especially easy to quickly install and remove in electronic equipment.
Product classification
According to foreign literature, toroidal transformers can be divided into three categories: standard, economic and isolation, etc. The characteristics of each category are:
Standard power transformer products
Series of 8 to 1500 VA capacity, with smaller voltage regulation rate, full load capacity and high efficiency. Small voltage adjustment rate, full-load operation temperature rise of only 40 ℃, allowing short-term overload operation, suitable for demanding applications. The primary and secondary windings are insulated with polyester film of class B (130℃), which requires at least three layers of insulating tape, and can withstand AC 4000V, 1min of voltage withstand test.
Economical power transformer products
Series capacity of 50 ~ 1500VA, in order to ensure the performance of the basis of efforts to reduce the cost for continuous operation without overloading of the use of occasions, the operating temperature rise of 60 ℃, the insulation material grade for the class A (105 ℃), when the full load when the output voltage error is less than 3%.
Isolation transformer product series
Capacity 50 ~ 1000VA, can be divided into industrial and medical equipment with two series. Isolation transformer focuses on its insulation performance, primary and secondary with B-class insulation between the polyester film wrapped at least 4 layers, breakdown voltage greater than 4000V, all primary must lead to the use of double-insulated wire. The maximum temperature rise of the transformer is less than 45 ℃.
Medical isolation transformer
Medical isolation transformer in addition to the above requirements, but also in line with the UL544 standard, that is, the primary and secondary windings should be thermally protected, the windings and grounded copper shielding spacing distance should be greater than 13mm.
1.Removal of the old winding
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With scissors, the insulation paper is cut to reveal the transformer's secondary winding, the secondary winding diameter is usually thicker, in the actual maintenance of very few cases of burned out, because of the number of turns is not too much, it can be a turn by turn to dismantle in order to count the number of turns. Multiple secondary windings can be taken in a similar way while dismantling the number of turns. Primary winding wire diameter is thin, burnt out more common. As the number of turns of the primary winding more than a thousand turns, coupled with the insulating material is melted and attached to the wire turns, if the above method is still used to count the number of turns, is obviously very troublesome. Quick method is: use scissors along the circumference of the center line of the primary group of coils layer by layer cut, and then cut the coil stripped core, and then count the number of roots that is the total number of turns. The method of cutting is shown in the figure.
2. Insulation of the toroidal core
The core of a toroidal transformer is usually made of high-quality, high permeability silicon steel tape. When the primary coil burns out, the insulation layer of the toroidal core impregnated with insulating varnish will be damaged to varying degrees at the same time, and it should be impregnated with varnish before rewinding the coil. The method is: the ring-shaped core immersed in insulating varnish, a few minutes after the removal of drying, and then dry in the oven. Then paste a layer of tape on each of the inner and outer circumference, and then the cellophane scratched into a strip about 2cm wide, the core wrapped around a layer, and use double-sided tape to adhere to the joints.
3. Line shuttle production
In order to facilitate manual operation, must make a special winding line prongs. I designed a "work" shaped wire shuttle, shown in Figure 2. It can be processed from plastic sheet or stainless steel sheet, can be taken for the single-stranded wire turns about 8 times the circumference, the width is less than the ring-shaped core inner diameter of about 2cm. Such a wire core is not only easy to wear around, but also reduce the number of times to wear around. Obviously, the enameled wire on the line shuttle around the length of a circle for the single-stranded wire turns perimeter of 8 × 2 = 16 times, if the use of double wire and winding, the line shuttle on each circle of the enameled wire can be in the ring-shaped core around 32 turns. The AV-228 professional power amplifier, for example, the primary coil of the toroidal transformer for 1068 T. Double parallel winding for 534 T, and thus the wire shuttle on the winding 534 ÷ I6 ≈ 34 turns of enameled wire will be enough.
4. Winding coil
first winding primary winding, and the original wire diameter similar to high-quality high-strength enameled wire, double-wire parallel winding in the "I" shaped shuttle, the number of turns to meet the requirements of the cut. Double wire head with double-sided adhesive on the outer circumference of the ring-shaped core, so that the wire shuttle in the ring-shaped core of the inner hole through the winding, as shown in Figure 3. After one layer of coil is wound, brush on a layer of insulating varnish (conducive to the positioning of the wire turns and insulation) and wrap it with cellophane before winding the second layer of coil. After winding, the head and tail of the two coils are connected to make the series connection, and the other two wires are welded with soft skin wire to lead out, and well insulated. Add a layer of interlayer insulating paper on the primary unity group and then wind the secondary winding, the winding method is the same as the primary winding method.
When all the windings are finished, the toroidal transformer into a constant temperature oven baking for a period of time, in order to dry the insulating paint. Then wrap the outermost layer with a thicker layer of insulating paper, and the toroidal transformer is finished.
The above is the introduction of all the production methods, it seems as if it is very complex, but as long as the requirements of the steps to complete or very simple, first of all, we should read the main points and operating procedures, understand the principle, and then according to the different needs and conditions of the production of different methods can be selected, each production method has its own unique features, I believe that these methods can meet the needs of all of us. I believe that when their own hands to make a successful toroidal transformer that mood will be very excited.