Measuring Riddle No.6 – CT & PT Circuit diagram

If we have 4-wire 3 phase or 3-wire 3 phase system (generator), how many CT & PT do we need for Ampmeter, voltmenter, power factor, etc.. measurement?? …
If we have 4-wire 3 phase or 3-wire 3 phase system (generator), how many CT & PT do we need for Ampmeter, voltmeter, power factor, etc.. measurements??

+ 3 CT and 3 PT or 2 CT & 2 PT or else??

I tried to search the topic on google, but couldn't get any usefull. Can someone please tell me.

Thanks,
bethy.