Abstract: An emulator which is able to operate on a standard single phase 120 VAC line, generates simulated three-phase alternating current in order to demonstrate the operation of a polyphase electricity meter. The emulator is also capable of demonstrating the operation of the polyphase electricity meter which has been incorrectly wired into the polyphase circuit, i.e., with incorrect or missing connections to the current transformers; or in which there are problems with the phasing of the polyphase circuit, i.e., incorrect phase differences between circuits or between the currents and voltages within any of the phases.

Abstract: A solid-state demand register is described for determining the maximum electrical-power demand made on an electric utility by a load. The register, which employs a microprocessor, provides noncumulative, cumulative, and continuous-cumulative electrical-power demand measurement capabilities. The microprocessor, operating under a control program stored in a read-only memory, employs computing constants and generates computed results. A nonvolatile read/write memory, which stores the computing constants and computing results, is of the type that retains stored data even when deenergized. These constants and results can be visually displayed by an optoelectronic display. Error detection and correction of data are performed by the programmed microprocessor by means of an eight-bit Hamming code.