Summing watt-hour transducer
AssigneeAllen-Bradley Company, Inc.
InventorJohn E. Callan
Life of this patent
Estimating the term…
Abstract
A summing watt-hour transducer is connected to a three-phase power line to monitor the energy being supplied to one load, and is connected to an ordinary watt-hour transducer that monitors energy supplied to a second load. A summing integrator circuit sums and integrates signals derived from the power line and the ordinary watt-hour transducer to obtain a voltage proportional to a unit of total energy demand. The summing operation is triggered by a signal from a control circuit that is responsive to contact closure pulses from the ordinary watt-hour transducer. Output signals from the summing integrator circuit are converted to contact closures for input of energy demand signals to an energy demand/schedule controller.
Claims10
A summing transducer for summing the energy consumption of a first load, which is connected to a plurality of power supply lines, and the energy consumption that is measured for a second load by an energy-monitoring device that generates an energy demand signal, the transducer comprising:
- power transducer means, coupled to the power supply lines, for generating a signal proportional to the instantaneous power being supplied to the first load;
- summing integrator means having two inputs and an output, one input being coupled to the power transducer means to receive the signal proportional to the instantaneous power supplied to the first load, and the other input being connected to receive a signal derived from the energy demand signal provided by the energy-monitoring device, the summing integrator means being responsive to the received signals for generating an output signal proportional to a unit of energy consumption for the two loads;
- control means adapted to be coupled to the energy-monitoring device, and responsive to the energy demand signal from the energy-monitoring device to generate a control signal;
- a capacitor;
- switch means connected between a voltage supply and the capacitor and connected between the capacitor and the second input on the summing integrator means for initially coupling the capacitor to the voltage supply to charge the capacitor to a value proportional to a unit of energy demand for the second load, the switch means being coupled to the control means and being responsive to the control signal therefrom to electrically couple the charged capacitor to the second input of the summing integrator means;
- and
- unit measuring means coupled to the output of the summing integrator means and responsive to the output signal therefrom for generating a signal representing the consumption of a preselected unit of energy by the two loads,
- whereby the discharge of the capacitor in response to its coupling to the second input on the summing integrator means provides a signal that can be summed and integrated with the signal from the power transducer means to generate the signal proportional to a unit of energy consumption for the two loads.
A summing circuit, responsive to an instantaneous power signal derived for a first load and responsive to an energy demand signal derived for a second load, for generating a pulse for a preselected unit of energy collectively consumed by the two loads, the circuit comprising:
- first means with an input at which the energy demand pulse is received for generating a control signal in response to the energy demand pulse;
- a capacitor;
- switch means, connected between a voltage supply and the capacitor, for coupling the capacitor to the voltage supply to charge the capacitor, the switch means being connected to the first means and being responsive to the control signal therefrom to couple the charged capacitor to a discharge path;
- summing integrator means with a first input that receives the instantaneous power signal derived for the first load, and with the second input which is coupled to the switch means through the discharge path to receive a signal generated by the discharge of the capacitor, the summing integrator means being operable to generate a voltage at its output that is proportional to a unit of energy being consumed by the two loads;
- and
- unit measuring means coupled to the output of the summing integrator means and responsive to an output signal therefrom for generating a signal representing the consumption of a preselected unit of energy by the two loads.
Dependencies are inferred from the claim text.