Emoncms feeds not recording correctly

I can’t get the above feeds to report correctly. I’m using grid for imported/exported power, solar for power from PV & consuming for whole house consumption so:
consuming = grid + solar (grid is +ve when importing & -ve when exporting power)
In my feeds printout grid = -9, solar = 694 & consuming = 640 but consuming should be -9 + 694 = 685.
Any suggestions where I’m going wrong?