Abstract: A system and method for generating an AC power output signal from a DC power input signal. The system incorporates a DC-to-DC boost regulator including a plurality of boost stages coupled in series for receiving a DC input signal and producing a boosted DC power signal. The system further incorporates a DC-to-AC converter coupled to the transformerless DC-to-DC boost regulator, for receiving the boosted DC power signal and generating an AC power output signal. A control element is coupled to both the DC-to-DC boost regulator and the DC-to-AC converter. In at least one embodiment, the system and method for generating an AC power output signal from a DC power input signal are used in connection with an uninterruptible power supply.
Abstract: A pump control system incorporates a programmed processor and responds to input from multiple floats. The programmed processor can respond to detected float failures in real time by reassigning control, lag, or lead functions from a failing float to one of the remaining functioning floats. Pump alternating functionality can be provided if any two of a plurality of four or more floats continue to function as expected.
Abstract: A redundant, modular pump system includes a plurality of substantially identical pump modules. Each module includes constant speed drive circuitry, variable speed drive circuitry and a pump. Expansion is accomplished by adding modules. Reliability is enhanced by being able to operate each pump at constant or variable speed irrespective of whether other modules are being operated at different variable or constant speeds. A common, software driven control element activates drives and other devices in the modules to provide fluid on demand at a pre-selected pressure.
Abstract: A system and method for generating an AC power output signal from a DC power input signal. The system incorporates a transformerless DC-to-DC boost regulator including a plurality of boost stages coupled in series for receiving a DC input signal and producing a boosted DC power signal. The system further incorporates a DC-to-AC converter coupled to the transformerless DC-to-DC boost regulator, for receiving the boosted DC power signal and generating an AC power output signal. A control element is coupled to both the DC-to-DC boost regulator and the DC-to-AC converter. In at least one embodiment, the system and method for generating an AC power output signal from a DC power input signal are used in connection with an uninterruptible power supply.
Abstract: A variable frequency motor starting system has a variable frequency AC power supply for generating an AC power output signal applied to an AC motor. A controller is coupled to the variable frequency AC power supply for producing a control signal for adjusting the frequency of the AC power output signal produced. Upon initially applying power to an AC motor or detection of a starting current for an AC motor, the controller adjusts the frequency of the power output signal applied to the AC motor. The frequency of the power output signal is adjusted to a value below the value of the typical operating frequency. The value of the frequency can be increased to the final operating value.
Abstract: A non-contact probe provides information as to relative amplitudes of harmonics of a current or voltage waveform as well as total harmonic distortion. The probe includes a non-contact sensor with an amplifier coupled thereto. Output signals from the amplifier are digitized and analyzed in a programmed processor. Output from the processor provides a display of relative harmonic amplitudes as well as an indicator of total harmonic distortion.
Abstract: A non-contact probe provides information as to relative amplitudes of harmonics of a current or voltage waveform as well as total harmonic distortion. The probe includes a non-contact sensor with an amplifier coupled thereto. Output signals from the amplifier are digitized and analyzed in a programmed processor. Output from the processor provides a display of relative harmonic amplitudes as well as an indicator of total harmonic distortion.
Abstract: A fluid pressure control system which is usable to control pressure in a fluid distribution system includes a variable speed drive coupled to a pump. A hydropneumatic tank is coupled to the distribution system. In normal operation, the variable speed drive actuates the pump so as to maintain pressure in the system. Under low flow conditions, a control unit, using the variable speed drive energizes the pump so as to pump fluid into and pressurize the hydropneumatic tank. The control unit then shuts off the pump. Pressure is maintained in the system, until a predetermined, lower, set point is reached as a result of pressure in the hydropneumatic tank.
Abstract: A fluid flow delivery system switches a variable speed pump drive among a plurality of pumps. The remaining pumps can be operated as constant speed pumps and can be energized one at a time in response to increasing demand. The pump associated with the variable speed drive can be operated over a variable output range to provide relatively low levels of fluid output, in response to low demand, and can be operated in combination with one or more constant speed pumps to provide increased levels of output fluid in response to greater demand levels.
Abstract: A method of making a building panel and the panel made by the steps which include laying a mold form horizontally, laying bricks in the pattern indicated in the mold form and depositing a fibrous and cementitious mixture in the spaces between the bricks and over the tops of the bricks. Providing a reinforcing lattice work and forcing it into the still soft cementitious mixture. Subsequently, a resin insulating material is foamed in situ in the mold cavities formed between the elements of the lattice work. Optionally, a smooth finish coat of material may be troweled or sprayed over the insulation material.
Abstract: A method for making a building panel and the panel made by the steps which include laying a mold form horizontally, laying bricks in the pattern indicated in the mold form and depositing a fibrous and cementitious mixture in the spaces between the bricks and over the tops of the bricks. Providing a reinforcing lattice work and forcing it into the still soft cementitious mixture. Subsequently, a resin insulating material is foamed in situ in the mold cavities formed between the elements of the lattice work. Optionally, a smooth finish coat of material may be troweled or sprayed over the insulation material.