A transformer is a device that utilizes the principle of electromagnetic induction to convert one AC voltage into another AC voltage with the same frequency
2. Classification of Transformers
According to the working frequency, transformers can be divided into various types, such as high-frequency transformers (also known as pulse transformers, switch transformers), low-frequency (power frequency) transformers, etc; According to their functions, transformers can be divided into step-down transformers and step-up transformers; According to the purpose, transformers can be divided into various types, such as power transformers, voltage regulating transformers, audio transformers, intermediate frequency transformers, isolation transformers, input transformers, output transformers, etc. The commonly used transformers in household appliances mainly include mains (power frequency) transformers and switch transformers. Their physical appearance is shown in Figures (a) and (b), and the circuit symbols are shown in Figure (c)
Transformer inspection
1. Power frequency transformer inspection
(1) Insulation performance inspection
Place the multimeter in "R × Measure the resistance values between the primary winding and each secondary winding, iron core, and electrostatic shielding layer at 10k "gear, and ensure that the resistance values are infinite. If the resistance value is too small, it indicates that there is leakage, which leads to poor insulation performance of the transformer
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