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NOTES ON CURRENT TRANSFORMERS

NOTES ON CURRENT TRANSFORMERS

A current transformer is a transformer, which produces in its secondarywinding a current, which is proportional to the current flowing in its primarywinding. The secondary current is usually smaller in magnitudethan the primary current.The principal function of a CT is to produce a proportional current at alevel of magnitude, which is suitable for the operation of measuring orprotective devices such as indicating or recording instruments and relays.The rated secondary current is commonly 5A or 1A, though lower currentssuch as 0.5A are not uncommon. It flows in the rated secondary load,usually called the burden, when the rated primary current flows in...

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