Answer / ahmed rahman

in this connections for over current protection,i have a strange theoretical question.
we all see the common wire of the cts secondaries.
in this wire , the 3 currents of the 3 phase pass through it,
i want to know how each current goes back to it's ct without going to another one however it has a way to pass through !
..the second part of my question,,this earth connection also to the secondaries of the cts, why the current doesn't pass through it?? what prevents it? it acts as a short circuit to the earth !!!

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