Explain construction and working of isolation transformer.

3 Answers

Answer :

Construction and Working of Isolation Transformer: 

Construction: 

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i) Isolation transformers are specially designed transformers for providing electrical isolation between primary & secondary windings. ii) The transformer has primary and secondary windings placed on the common core limbs which have equal number of turns so that the voltage fed to the primary is available at the secondary without any change in its magnitude. iii) These are built with special insulation between primary and secondary. 

Working: When supply is given to primary it causes primary current to flow in primary winding and inducing ac fluxes in core. The secondary winding is wound on common magnetic core, hence these ac fluxes are linked with it. Now secondary emf is induced according mutual induction action and secondary current flows through load if connected.

Answer :

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i) The construction & working of isolation transformer is nearly identical to conventional transformers. ii) Isolation transformers are specially designed transformers for providing electrical isolation between the power source and the powered devices. iii) The transformer has primary and secondary windings placed on the common core limbs which have equal number of turns so that the voltage fed to the primary is available at the secondary without any change in its magnitude. iv) Any spikes on the primary side are subdued and prevented from getting transformed to the secondary side to a very large extent thus protecting the devices or loads connected to secondary side. 

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v) These are built with special insulation between primary and secondary. vi) It acts as a decoupling device. vii) These transformers block the transmission of direct current (DC) signals, but allow AC signals to pass from one circuit to another. 

Answer :

 Isolation Transformer

https://youtu.be/gq9kjLlhPN0

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