Help with rule to correct consumption

The production of one (out of 3) inverter is seen as consumption in my (https://pvoutput.org/edit.jsp?sid=49339) system.

Can I correct the consumption using a rule like eg

If (out) consumption = consumption - 15/(15+25+25)*power

What is wrong with the syntac?

The rule won’t allow consumption / generation to be used in the rule statement. i.e. when applying the rule on generation power, the consumption power is not accessible and vice versa.

The ‘power’ variable refers to the current power value, either generation or consumption.