Abstract: Electronic systems for controlling submersible pumps are provided herein. In certain configurations, a pump system includes three or more submersible pumps used for pumping fluid from a reservoir, sensors used for generating sense signals indicating a fluid level of the reservoir, and a control circuit for selectively activating the pumps based on the sense signals so as to control pumping of fluids from the reservoir. In certain implementations, the control circuit is operable in a plurality of user-selectable operating modes associated with different pump activation sequences in response to the fluid level of the reservoir rising.

Abstract: Electronic systems for controlling submersible pumps are provided herein. In certain configurations, a pump system includes three or more submersible pumps used for pumping fluid from a reservoir, sensors used for generating sense signals indicating a fluid level of the reservoir, and a control circuit for selectively activating the pumps based on the sense signals so as to control pumping of fluids from the reservoir. In certain implementations, the control circuit is operable in a plurality of user-selectable operating modes associated with different pump activation sequences in response to the fluid level of the reservoir rising.

Abstract: Apparatus and methods for electronic monitoring of ozone generators are provided herein. In certain configurations, an ozone generator includes ozone generation circuitry for producing ozone and a control circuit that monitors the ozone generation circuitry to determine whether or not ozone is being properly produced. The control circuit includes an AC input that receives power from an AC power supply and one or more AC outputs for providing AC output voltages to the ozone generation circuitry. The control circuit further includes one or more AC current sensors used to monitor a status of ozone production by monitoring AC current flowing into the ozone generation circuitry via the control circuit's AC outputs. The control circuit alerts a user of the status of ozone production while avoiding a need for the user to test a treatment fluid for ozone concentration and/or manually inspect or test components of the ozone generator.

Abstract: A capacitor-charging series resonant mode, high voltage power supply (SRMPS) (10) includes a switching network (30) that alternately applies a positive and negative voltage to a series resonant circuit, comprising a resonant capacitor and inductor. The inductor may include the primary winding (14) of a power transformer (12). The switching action occurs at a fixed frequency above the audible range. This frequency is approximately the resonant frequency of the series resonant circuit. The switching action causes sine wave quantums of current of alternating phase to flow through the primary winding. Secondary windings (16) of the transformer are coupled through a suitable rectifying network (18) to charge a load capacitor C.sub.L to a high voltage. During a first mode of operation the load capacitor is charged at a maximum rate. During a second mode, the load capacitor is charged only as needed to maintain a desired charge thereon.

Abstract: A full wave bridge inverter includes four switch arms, each including N bipolar, parallel transistor switching elements. During a first interval, emitter-collector paths of all transistors in the first and second arms are forward biased so current flows in a first direction from a DC source through a bridge diagonal. During a second interval, emitter-collector paths of all transistors of the third and fourth arms are forward biased so current flows from the source through the diagonal in a second direction. The transistors have a tendency to be activated into the conducting and cut-off conditions at different times, and different transistors have a tendency to conduct differing amounts of current while forward biased. To overcome these tendencies, there are 2N.sup.2 transformers, each including first and second windings having like numbers of turns.