Tips to design an analog automatic switch selection circuit for CT (Current Transformers)

How can I simulate it on ltspice? You guys can help me to understand secondary of this ct? Its because its weird 0.72R I thought only when u have voltage source u need a series resistance and for current source need a parallel resistance to take measurements for a non-ideal sources. So you have 5A current source on secondary, this is what means 5A on diagrama? Another point is why (6.3V 8A) on secondary inductor of ct, where this value came from? Its like if you have sct013-100 (100A:1V) Which difference between yhdc (100A:1V) and (100A:0.33V) in terms of calculations?