Spaces Color

Good day

When looking at the "Output Preview" under Separations, I am seeing the CMYK options but I am also seeing a option called "Spaces Color" under Spot Plates.

Spaces Color doesn't  show any colors when I switch it off, but it is influencing when I output the Color Bar on my CTP.

Can anyone time me what the function is of "Spaces Color"

regards Riaan