Introduction to Transformers
Electrical Q&A Part-3
Questions and Answers related to Transformer:
1. What is a transformer and how does it work? * A transformer is an electrical apparatus designed to convert alternating current from one voltage to another. It can be designed to “step up” or “step down” voltages and works on the magnetic induction principle. * A transformer has no moving parts and is a completely static solid state device, which insures, under normal operating conditions, a long and trouble-free life. It consists, in its simplest form, of two or more coils of insulated wire wound on a laminated steel core. * When voltage is introduced to one coil, called the primary, it magnetizes the iron core. A voltage is then induced in the other coil, called the secondary or output coil. The change of voltage (or voltage ratio) between the primary and secondary depends on the turns ratio of the two coils.
2. What are taps and when are they used? * Taps are provided on some transformers on the high voltage winding to correct for high or low voltage conditions, and still deliver full rated output voltages at the secondary terminals. * Standard tap arrangements are at two-and-one-half and five percent of the rated primary voltage for both high and low voltage conditions. * For example, if the transformer has a 480 volt primary and the available line voltage is running at 504 volts, the primary should be connected to the 5% tap above normal in order that the secondary voltage be maintained at the proper rating.
3. What is the difference between “Insulating,” “Isolating,”and“Shielded Winding” transformers? * Insulating and isolating transformers are identical. These terms are used to describe the isolation of the primary and secondary windings, or insulation between the two. * A shielded transformer is designed with a metallic shield between the primary and secondary windings to attenuate transient noise. * This is especially important in critical
Questions and Answers related to Transformer:
1. What is a transformer and how does it work? * A transformer is an electrical apparatus designed to convert alternating current from one voltage to another. It can be designed to “step up” or “step down” voltages and works on the magnetic induction principle. * A transformer has no moving parts and is a completely static solid state device, which insures, under normal operating conditions, a long and trouble-free life. It consists, in its simplest form, of two or more coils of insulated wire wound on a laminated steel core. * When voltage is introduced to one coil, called the primary, it magnetizes the iron core. A voltage is then induced in the other coil, called the secondary or output coil. The change of voltage (or voltage ratio) between the primary and secondary depends on the turns ratio of the two coils.
2. What are taps and when are they used? * Taps are provided on some transformers on the high voltage winding to correct for high or low voltage conditions, and still deliver full rated output voltages at the secondary terminals. * Standard tap arrangements are at two-and-one-half and five percent of the rated primary voltage for both high and low voltage conditions. * For example, if the transformer has a 480 volt primary and the available line voltage is running at 504 volts, the primary should be connected to the 5% tap above normal in order that the secondary voltage be maintained at the proper rating.
3. What is the difference between “Insulating,” “Isolating,”and“Shielded Winding” transformers? * Insulating and isolating transformers are identical. These terms are used to describe the isolation of the primary and secondary windings, or insulation between the two. * A shielded transformer is designed with a metallic shield between the primary and secondary windings to attenuate transient noise. * This is especially important in critical