Directional clamp showing negative value

I have finally got hold of a directional clamp.
its a smappee ct clamp
I was hoping that a directional clamp would show export as a negative value but it seems to be the same no matter the direction its clipped onto the wire.

due to the inverter location and placement there's no way I can separate the feeds or record them separately and I don't want to have 2 flukso to record it. so needing some sort of way to measure both with one clamp
the only way I can see is if the clamp outputs a negative value for export and I though I read somewhere about it doing that but it doesn't seem to work.
https://www.flukso.net/content/display-negative-values-flukso-dash

If it can do negatives what clamp do I need?? I haven't been able to get any flukso ones.