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winlad:
Energy is force times distance. KWH is energy. Put a watt-meter on your machine. Next you need some way to calibrate this in terms of tonnage. One needs to work with the same lift height. You also need the no load energy and other losses.
As an alternative. Measure the current for an empty load and we will assume you always operate at constant velocity. Then measure the current for a known load. Assume voltage is constant. Load current minus no-load current is actual current from the load, and this should be approximately equal to the amount of load. Create a calibration constant from current to load.
Measure current for each load. Add all these up that occur in your desired 1 hour period.
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