Abstract: A device for controlling power to electrically powered equipment. The device includes one or more receptacles for engaging a first power line providing power to the electrically powered equipment. The device includes a second power line for receiving AC power from an AC power source. The device includes one or more switches for selectively interconnecting one of the receptacles to the fist power line. A control circuit controls operation of each of the one or more switches in an allowance mode, non-allowance mode, and in a timed-on mode. In the allowance mode, the control circuit controls the one or more switches so that the electrically powered equipment can only be energized between specified times. . In an non-allowance mode, the control circuit controls the one or more switches so that the electrically powered equipment cannot be energized between specified times.

Abstract: A method of operating a relay includes shifting, by a predetermined time increment each time the relay coil is energized, the time in the sine wave of the applied AC power source at which the relay coil is energized. The method further provides for similarly shifting the time in the sine wave at which the relay coil is de-energized. When applied to a system having two relays, the method includes providing such shifting to both relays and further includes providing a predetermined time delay between the time one relay is de-energized and the other relay is energized.

Abstract: In a digital thermostat powered solely by batteries, when the battery voltage drops to a predetermined value, the thermostat effects a visual indication of the existence of a low voltage condition. If the batteries are not replaced within a predetermined time period thereafter, and the battery voltage remains adequate to operate the thermostat, the temperature setpoint is automatically altered by being lowered, if in the heating mode, or being raised, if in the cooling mode. The change in room temperature resulting from the change in temperature setpoint should prompt the user to replace the batteries. By proper manipulation of user operable means, the user can subsequently cancel the altered temperature setpoint and re-establish the desired temperature setpoint so as to provide for normal thermostat operation for a predetermined time period during which the batteries can be replaced.

Abstract: A self-resonating power supply for controlling operation of an electrostatic air cleaner wherein the ouput voltage to the cell is limited to a desired value by means of a regulated feedback circuit so as to prevent nuisance arcing in the cell and to minimize generation of ozone. The feedback circuit detects changes in the output voltage and responds to such changes by changing the biasing of a switching transistor so as to cause the output voltage to return to the desired value.