A substantial cost for operating most oil properties is the monthly electricity charge. Analyzing the motor current in a beam pumping system is a difficult task in that the current is normally changing from consumption to generation during each pump stroke. A gear "slap" will occur during a pump cycle when the motor changes from driving the pumping system to being driven by the counterbalance and the unit's inertial forces. Conventional clamp-on current meters indicate the magnitude of the current flow in the wire but do not indicate whether the motor is consuming or generating electricity.
A new computerized technique for acquiring motor current using a clamp-on probe permits the acquisition of apparent current and the calculation of real ( or active) current. The apparent current is acquired at a one kilohertz rate. These data are processed to obtain real current A plot of the active current ( showing consumption and generation) along with the apparent current is presented to the user. This plot is extremely beneficial for determining electricity costs, pumping unit balance, cost per barrel of oil lifted and other power consumption factors.