Measures the electric power p flowing from 'term_p' to 'term_n' and the total heat inflow q at term 'heat'. The efficiency eta in % is then defined by
eta = 100*(p - q)/p if arrow points into the measured component and q < abs(p) eta = 100*p/(p + q) if arrow points out of the measured component and q < abs(p) eta = 0 elsePositive values of eta indicate powerflow in direction of arrow, negative values of eta indicate powerflow against direction of arrow.
Note: Take care about the above definitions if approximations are used in measured components.
In problematic cases use power sensors electrical and mechanical.