Multiple rate electrical energy metering system and method

Abstract

An electronic time-of-day metering system is disclosed for measuring electrical power by at least two different mechanical recording devices depending on the time-of-day and time of week in which the electrical power is being consumed. A conventional kilowatt hour meter includes a set of decade gear driven dials which register the kilowatt hours consumed on a continuous basis. At least one other set of decade gear driven dials is provided for registering the consumption of kilowatt hours during preselected peak power usage intervals. A single MOS integrated circuit controls the operation of the alternate set of decade gear driven dials. This circuit utilizes as its time base the 60 Hz line voltage derived from the energy distribution system being metered. A clock circuit generates timing signals for a clock control circuit which includes a circulatory memory which is preprogrammed to contain the times at which one or more alternate sets of dials are to be actuated. When the clock time equals a stored time a gating signal is generated. At the same time a function command signal, also stored in the circulatory memory, is passed through the enabled gate for engaging or disengaging the alternate set of decade gear drive dials, depending on the value of the function stored. The gated signal controls the energization of a bistable clutch which engages the alternate set of dials. A method for registering total energy consumed by a metered system as well as energy consumed during preselected time intervals is also disclosed.