ABSTRACT
Electricity flows from a source of high potential to low potential. Electrical potential is measured in volts or voltage. As a consequence, if the load on each of the three legs is exactly equal (that is, each one of them has an equal number of watts taking power from it) then the current flow on the neutral will be zero. Power for film and video production usually comes from one of three sources: stage service, generators, and tie-ins. A fourth method—wall plugging is only feasible for smaller productions where only a few low wattage lights (such as LEDs) are used for a scene. Once the power is up, one major responsibility remains, balancing the load. Simply put, keeping a balanced load means keeping a roughly equal amount of current flowing on all legs, whether it be a three-wire or a four-wire system. The ‘ebb and flow’ of the non-productive power increases the current in the line.
