Abstract: A method for permitting an on-site diagnosis of the performance and/or production activity of one or more unit(s) of electrical equipment in a facility to determine if power is being wasted, comprising the steps of measuring the electricity consumptions of the unit(s); displaying time with a fixed relationship along two different coordinates of two separate, intersecting axes; dividing the time displayed into time segments corresponding to the operation times of the unit(s) over first and second time intervals for the respective coordinates, where the first time interval's time segments correspond to one or a small number of the second time interval's; and displaying the unit(s)' measured electricity consumptions, for each time segment, at each intersection of the two time coordinates such that an on-site determination of the operating condition of the electrical equipment unit(s) becomes visually apparent from the display.