methods and apparatus for supplying power for use in metering electrical energy over a wide range of voltages with a single meter are disclosed . the wide ranging meter includes a processing unit for processing divided input voltage and a current component in order to determine electrical energy metering values . the processing unit is operable in response to supply voltages . a power supply , connected to receive the undivided voltage component , generates the supply voltages over the wide dynamic range . it is especially preferred for the power supply to include a transformer having first , second and third windings , wherein the undivided voltage component is provided to the first winding and wherein the second winding defines the output of the power supply . a switching member is connected to the first winding for permitting and preventing the flow of current in response to a control signal . a control member generates the control signal in response to the output of the power supply . it is also preferred for the control signal to disable the witch member . it is further preferred for the power supply to include a voltage blocking clamp , connected to the transformer for blocking the voltage applied to the transformer . it is still further preferred for an oscillator to be used to generate an oscillating signal for switching the switching member on and off so that the switching member is provided a substantially constant off time .