Abstract: A power stealing system having a switch and a circuit that takes power from equipment to operate control electronics. The system may be such that power stealing occurs while the equipment is not powered to avoid disruption or false signals in the electronics or equipment. The circuit may convey taken power to a storage device. The electronics may be powered by the storage device. The storage device may have a capacitor, a rechargeable battery, a non-chargeable battery, a solar cell, fuel cell, line power, and/or the like.

Abstract: A switch state assurance mechanism of a power stealing circuit for connection to a thermostatically controlled or other kind of operational system. The mechanism may be an interface for the power stealing circuit to the operational system. A switch or relay of the mechanism may have several states but have an appropriate state for a given status of the power stealing circuit and the operational system. The switch or relay may have a latching characteristic relative to its states. The mechanism may have a detection circuit and a drive circuit connected to the relay, and a control circuit connected to the detection circuit and the drive circuit. The mechanism may check the relay state and change the relay to a desired state. The mechanism may be incorporated in other circuits beside a power stealing circuit.

Abstract: Electronic devices that include batteries can be adapted to provide one or more indications of a low battery condition. An electronic device such as a controller can include a battery and can be adapted to determine a first low battery condition. A first indication can be provided in response to the first low battery condition. In some cases, a second battery condition can be determined and a second indication can be provided in response to the second battery condition. The indications provided to the user can be made progressively more noticeable over time, until the battery is replaced.

Abstract: A thermostat includes a number of control parameters including a temperature set point, a selected cycle rate, a room temperature swing setting, and/or any other suitable control parameter. In one illustrative embodiment, the thermostat includes a push button for providing a signal each time it is depressed and a controller coupled to the push button. The controller is adapted to receive a sequence of one or more signals from the push button, and is further adapted to set a control parameter such as the cycle rate or room swing setting to a value that corresponds to the sequence of one or more signals. In another illustrative embodiment, the thermostat includes a mechanical user interface such as a rotating selector or slider. The thermostat is adapted to receive a signal that relates to the current position of the mechanical user interface, and sets a control parameter of the thermostat based thereon.