There are two types of transformers in the market-linear transformer and switching power supply. The transformers design is different. Sometimes it comes only as an AC adapter. Linear transformer mostly in radio, project kits is used, VCD and etc while switch mode power transformer, monitor, TV, fax and find more.
A transformer winding is made up of two or more coils on the same core. For transformers, the material is usually iron. For a radio-frequencyTransformer, the material is usually ferrite or air. The fundamental property of a transformer is to change AC voltage. A transformer can not change the DC. A transformer has a lower voltage AC output voltage at its secondary to its primary AC input. In contrast, a step forward with a transformer secondary voltage than primary. The transformer laminations or coatings of shellac, varnish or paint is to isolate short circuits between adjacent turnsWinding. I do not want to go too into detail on the operation of the transformer and the calculation of the transformer as you can read more details from books and electronic transformers.
How to test transformers: Transformer failures are relatively rare in most electronic devices, in comparison with other components. If current is too winding, the winding heats up and can fully open or break the isolation between the coils of wire can, so much so that the coilshort, in whole or in part.
Just as a coil, it is possible the continuity of a transformer primary winding or secondary. The real value of DC resistance you read is pretty useless, but at least you know if a winding is open. Linear control of the transformer is quite simple. Take the alternating voltage across the primary winding and the output voltage provided on the secondary side. No or low output voltage means the transformer winding has open or shorted winding. SearchSigns of overheating, such as black or dark areas or a burning smell.
On how to test a power transformer: it is a little 'complicated. You can not change voltage equipment and expect the desired output will be on the secondary side without connect to load otherwise over voltage (because you all of the secondary load removed) and the power section which consist of power fet, pwm ic Shock and switching power supply, etc. are designed to operate with load whilelinear transformation can occur without a charge.
The best way to test a switch mode power transformer is first removed from the Board of Directors. Check only the primary winding as secondary failures are very rare. How do we know what the primary? Track to see the large filter cap pin positive, the circuit goes. This is going to a pin of the transformer. Then try unloading power FETs is the central pivot and will lead to another pinTransformer. These two pins is the primary of the transformer. Check the resistance of the primary can only show if it is open, but can not verify that it has developed a shorted winding. Only by a ring test to determine whether short-or less. A short circuit in the primary may turn to blow the power section.
The tester ringer cheapest I found is Dick Smith LOPT METER or flyback tester. Simply connect the probes to the primary winding andThe result is immediately seen by the LED bar display. 4-8 bar represent a good winding, 1-2 bar represent partially and briefly turns off when the LED means that there is a serious short circuit winding. Besides checking the transformer can be used for B + COIL, horizontal yoke coil and flyback primary control and ballast (choke).
The tester is expensive ring Sencore equipment. Sencore LC102 and LC103C Besides checking capacitor that also have the opportunity to review all types of winding.Whether it's a low-voltage transformer, high voltage transformers, power transformer, pulse transformer, electric transformer, custom transformer this equipment can examine and test.
If you do not want to invest on this tester, you can use a bulb check. Remove one of the primary winding pin and connect a 60-watt bulb. One end of the circuit, while the other pin of the transformer. If the light goes out and does not suspect a shorted winding and if theexpires, the coil is in order.
Transformer repair is not easy and requires a good ability to do so. Most of the workshop transformer winding as a pretty big fan, car alternator starter motor and rewind. Switching mode power transformer is a bit 'hard to go back, because of the small size and low price.
