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Showing posts with the label primary current

How and Why an increase in secondary or load current causes an increase in primary current?

                                               If we connect a load to the secondary of the transformer as shown in fig-1, the induced emf in the secondary, causes the current   to flow in the secondary winding. At the instant shown in the diagram, the source of power causes the upper terminal of the primary to be positive, and the instantaneous direction of current is given by . In accordance with Lenz’s law, the secondary induced emf and the current it causes must be in such a direction as to oppose the setting up of the flux . Application of the right hand rule will show that this secondary current direction is given by. We now have a magnetomotive force in   the secondary. , opposing that of the primary . It must be remember...