Abstract: A pump control system incorporates one or more solid state level sensors as well as solid state pump control switches. Elimination of mechanical or electrode-mechanical parts by using ultrasonically based fluid level sensors as well as solid state switches for motor control enhances reliability and results in reduced power consumption and dissipation.

Abstract: An uninterruptible power supply system senses quality of available three phase input power and determines if load requirements can be met therefrom. If not, it drives an inverter to generate acceptable quality three phase AC to supply to the load. In this mode, the energy is obtained from a battery array. A solar panel can be used as a primary or a secondary source of input energy.

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 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.