Current Transformer Question. Usage:Solar Panel v grid electricity aas measured at meter
You can't.

How is the current transformer supposed to know which way is which? It has no way of telling the difference between current flowing the "wrong way" and being clamped onto the wire backwards from how you expected.

You can certainly ignore readings below zero in your measurement device, or possibly even clamp the reverse voltage with a diode. But there's no way to figure out which direction is which without some other source of information.