Abstract: A digital rod control system that employs separate power modules to energize the respective coils of a magnetic jack control rod drive rod drive system so that two, independently powered grippers can simultaneously support the control rod drive rod when it is not in motion to avoid dropped rods. The basic building block of the system is two or more selecting cabinets which receive multiplex power from at least one moving cabinet and are under the control of a single logic cabinet. Each of the cabinets include monitoring features to confirm the reliability of the system.

Abstract: A digital rod control system that employs separate power modules to energize the respective coils of a magnetic jack control rod drive rod drive system so that two, independently powered grippers can simultaneously support the control rod drive rod when it is not in motion to avoid dropped rods. The basic building block of the system is two or more selecting cabinets which receive multiplex power from at least one moving cabinet and are under the control of a single logic cabinet. Each of the cabinets include monitoring features to confirm the reliability of the system.

Abstract: A sine wave generator which utilizes a PROM for storing a predetermined bit pattern which is converted to a corresponding pulse waveform generated in response to a very accurate and stable clock pulse. The pulse waveform is shifted to a very exacting voltage level and is filtered by a band-pass filter to derive the desired fundamental frequency sine wave. The amplitude and frequency stable sine wave may be utilized in linear variable differential transformer (LVDT) apparatus for measuring the position of a controlled object such as a turbine valve. The arrangement may also be utilized for generating additional sine waves bearing some predetermined phase relationship with respect to one another for other control or signal processing applications.

Abstract: A turbine control system which includes dual controllers having microcomputer processing circuits and capable of transmitting and receiving digital information to and from a plurality of valve position control circuits, also including their own microcomputer circuitry for controlling turbine steam admission valves. An operator's panel provides for two levels of automatic control as well as a manual backup which is communicative directly with all of the valve position control circuits. Overspeed protection control as well as fast valving is provided by redundant speed control circuits.

Abstract: A distribution network power line communication system which is divided into addressable communication zones defined by repeaters located at the distribution transformers of the distribution network. Each repeater, when uniquely addressed by an interrogation signal from an interrogating source, strips its address from the interrogation signal and sends the resulting modified interrogation signal to its associated remote communication terminals, by-passing the associated distribution transformer. A timely, error-free response signal from a remote communication terminal is modified by a repeater to include the repeater address, and the modified response signal is sent back to the interrogating source. The binary base band interrogation and response signal information is preferably pulse width modulated to provide a self clocking format, and this self clocking signal is passed through two stages of frequency modulation to provide a signal which makes the receivers thereof substantially immune from drift.