Abstract: Modular tankless water heater apparatus designed for use in a system including a water supply conduit and a hot water conduit. The apparatus includes a heating tube assembly with a plurality of tubes positioned in parallel juxtaposition and connected adjacent the ends into a series connected configuration to form a continuous fluid passage. A heating element is enclosed in each tube and extends between the ends with each heating element including an electrical connector and an electrical control. A programmable electrical power controller is connected to the electrical controls of the heating elements and to flow sensor and heat sensor apparatus positioned in the continuous fluid passage. The controller is programmed to activate the electrical controls one at a time in response to a demand signal from the flow sensor and heat sensor apparatus.

Abstract: A fluid heating system with a heat exchanger includes an elongated cylindrical tube with an inlet end and an opposed end. An array of film resistive elements is positioned on the outer surface of the cylindrical tube and extends circumferentially at least partially around the outer surface. A spiral channel guide is coaxially positioned within the cylindrical tube so as to force fluid flowing in the tube into a spiral path at least partially against an inner surface of the cylindrical tube. The spiral channel guide directs fluid flowing in the cylindrical tube so as to cause turbulence to occur in the flow and increase thermal transfer from the inner surface of the cylindrical tube to the fluid flowing in the tube.

Abstract: An intelligent demand controller protects the local customer premises supply transformer from overload and senses conditions on the transformer. The intelligent demand control system utilizes a communications network with a plurality of load control units having a unique address and residing at a plurality of customer premises. A demand controller monitors the voltages and frequency of electricity provided to the customer premises as well as the instantaneous current required by the operating loads of the customer premises. Each of the plurality of demand controllers may be associated with one or more of a plurality of load control units and configured to receive data related to the state of the power supplied to the plurality of controlled loads and generate a transmit message using a predefined communication protocol. When certain programmable conditions are met, a load control unit is signaled to remove power from one or more of its monitored loads.

Abstract: A power management system comprises a microprocessor and a current flow sensor in electrical communication therewith. The current flow sensor measures the amount of electrical current available to the building as well as the actual current flowing through the building. A load sensor is in electrical communication with the microprocessor and measures the load requirements of the appliance. One or more switches are electrical communication with the microprocessor and control the power flowing to the appliance. The microprocessor maintains a record of the information from the load sensor and the current sensor and further has a electrical maximum limit and a continuous load limit for the building. The microprocessor uses the one or more switches to average a continuous load over a preset period of time which is less than the continuous load limit for said building while never exceeding the electrical maximum limit for said building.

Abstract: A compact tankless water heater of modular configuration to accommodate a range of potential demands is disclosed. A heat transfer chamber is divided into subchambers, each of which may may mount more than one heating element. Notched passageways at the top of each dividing wall allow water passage between chambers, and a plurality of temperature sensors act in concert with a flow sensor and microprocessor control of the heating elements to maintain a constant set point output water temperature.

Abstract: A communication system is connected to a pair of telephone conductors which supply telephone service to a telephone subscriber. An optically coupled switch connects a first winding of a transformer across the telephone conductors. A second winding of the transformer is connected to a modem for communicating over the telephone conductors via the transformer. A voltage sensor circuit senses the voltage across the telephone conductors and detects a reduction in the voltage level across the conductors which indicates an off-hook condition of a telephone unit of the subscriber connected to the conductors. The voltage sensor circuit also detects the presence of a ring signal on the conductors. The switch is periodically opened so as to disconnect the transformer from the telephone conductors, and permit the voltage sensor circuit to check for an off-hook condition.

Abstract: A solid-state control system for the control of a collector array, the system incorporating a sun-tracking mode, de-focusing at excessive temperatures, returning to a stand-by position after sunset, and prepositioning at sunrise.