What is the need for checking knee point voltage for CT's?

Answer Posted / iamdon

CT is designed for operation in linear region.In this
region only, current changes acoording to turn ratio.Knee
point on magnetisation curve of core is the point at which
core begins to saturates.Once the core gets saturated, it
losses the transformation propery.It will carry same
secondary current for all primary current.This maloperation
is of no use as far as CT action is concerned.

Knee point sets the upper limits of B so as not to exceed
this limit during operation.Thus it ensures the intended
operation of CT.

Author:arbelectbit@yahoo.com

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