Abstract: A thermostat or other in-line, two-conductor control device employs a power-stealing technique to obtain DC power for its electronic controls where the thermostat wire run has an R wire but no C (common) wire. The controlled switch for a reactive load, such as the gas valve relay or compressor contactor, is formed of a pair of power capacitors and a pair of switching transistors or other electronic controlled switches. The conductors for feeding DC power to control electronics are connected with the junctions of the power capacitors and their respective switching transistors. The power capacitors and switching transistors can be configured in respective series combinations, with the series combinations forming a parallel combination.

Abstract: A thermostat or other in-line, two-conductor control device employs a power-stealing technique to obtain DC power for its electronic controls where the thermostat wire run has an R wire but no C (common) wire. The controlled switch for a reactive load, such as the gas valve relay or compressor contactor, is formed of a pair of power capacitors and a pair of switching transistors or other electronic controlled switches. The conductors for feeding DC power to control electronics are connected with the junctions of the power capacitors and their respective switching transistors. The power capacitors and switching transistors can be configured in respective series combinations, with the series combinations forming a parallel combination.

Abstract: A method of configuring a device includes associating a network-connectable device (such as a Wi-Fi thermostat) with a first identifier (such as a first account) established on a network server; using a mobile communication device (such as a smartphone), accessing the network-connectable device using the first identifier, and setting or verifying in the network-connectable device one or more operating parameters (such as a set-point) of the network-connectable device; after setting or verifying the one or more operating parameters, removing the association of the network-connectable device with the first identifier, and permitting association of the network-connectable device with a second identifier (such as a second account) established or to-be-established on a network server and access to the network-connectable device and verification or setting of the one or more operating parameters of the network-connectable device using the second identifier.

Abstract: A thermostat, of the type that employs latching relays to connect thermostat power to the various wires of the thermostat run, has a re-pulse feature that supplies latching pulses at a given interval, e.g., three hours, to ensure that the relays are in their proper state agreeing with the thermostat mode and the room temperature relative to the setpoint(s). In the case that the room air temperature is changing in a manner contrary to the current heating or cooling mode, which may indicate the latching relay has been knocked or bumped and needs to have its proper state re-established, the thermostat microprocessor issues pulses to the latching relay(s) more frequently, e.g., each 30 minutes, and the re-pulses may have a longer pulse width, e.g., increased from 20 ms to 25 ms.

Abstract: A touch-screen control panel interface has a dielectric flat or curved front panel and a printed circuit board with a front side and a reverse side which is the component side. Alphanumeric display module(s) or an LCD display and optional protective cap mounted on the reverse side of the circuit board are visible through window cutout(s) on the board. An array of LED indicators can be mounted on the back side of the circuit board and visible through cutouts in the board. Metallized capacitive pads on or adjacent the back side of the front panel at touch locations permit selection of various modes, functions, and settings. These pads may be formed on the flat front side of the circuit board, on the back of the front plate, or on an intermediate membrane. A microprocessor is connected with the various components and with capacitive pad. Icons may be printed onto the flat panel, in registry with the metallized capacitive electrode pads.

Abstract: A furnace controller circuit includes a microprocessor with input ports and output ports including ports to issue control signals for actuation of inducer, gas burner, and furnace blower. A temperature-actuated limit switch commences a furnace shut-down sequence when the temperature of the furnace heat exchanger exceeds a predetermined limit temperature, and then resets to permit a turn-on sequence. An LED visible fault indicator is coupled to the microprocessor to provide visible fault messages. A non-volatile memory device coupled with the microprocessor is operative to store fault indications when present. In the event of power restoration after power failure, the limit switch status and other fault status are maintained. A lockout period is computed based on length of furnace run time until fault and recent fault history. Limit switch and other safety faults are recorded and these can be weighted and ranked based on age of each fault occurrence.

Abstract: A battery powered thermostat senses a battery voltage drop to a low-battery voltage level. At that point, the thermostat microprocessor provides a LOW BATTERY alert message, visible on the thermostat display. If the occupant fails to replace the power cells or does not notice the LOW BATTERY message, when the battery voltage drops further the microprocessor alters the thermostat set points. This reduces the number of heating or cooling cycles per day, and reduces the number of actuations of the latching relays in the thermostat, conserving remaining battery life. At a further drop in battery voltage the set points are changed additionally. Additional functions, such as second level heat, second level cooling, and fan speed, are disabled. The change in heat or cooling cycles induces the occupant to check the thermostat where he or she will notice the LOW BATTERY message.

Abstract: A touch-screen control panel interface has a dielectric flat or curved front panel and a printed circuit board with a front side and a reverse side which is the component side. Alphanumeric display module(s) or an LCD display and optional protective cap mounted on the reverse side of the circuit board are visible through window cutout(s) on the board. An array of LED indicators can be mounted on the back side of the circuit board and visible through cutouts in the board. Metallized capacitive pads on or adjacent the back side of the front panel at touch locations permit selection of various modes, functions, and settings. These pads may be formed on the flat front side of the circuit board, on the back of the front plate, or on an intermediate membrane. A microprocessor is connected with the various components and with capacitive pad. Icons may be printed onto the flat panel, in registry with the metallized capacitive electrode pads.

Abstract: A user interface of a controller has multiple touch-sensitive input transducers, e.g., capacitive pads. The pads are dynamically indicated: When any given touch sensitive input device is needed for input at a given step of the programming operation, an associated light source illuminates that input device so it is visible to the user. Those touch-panel input devices not needed for that are left unilluminated, and the microprocessor ignores any input from those input devices. At each step of the operation or programming of the controller, only those input transducers for the inputs that are permitted or relevant to that state are indicated. Correspondingly, only the inputs that are generated by actuating the input transducers for the valid (i.e., permitted or relevant) inputs results in a change in the state of the program in the microprocessor.

Abstract: A battery powered thermostat senses a battery voltage drop to a low-battery voltage level. At that point, the thermostat microprocessor provides a LOW BATTERY alert message, visible on the thermostat display. If the occupant fails to replace the power cells or does not notice the LOW BATTERY message, when the battery voltage drops further the microprocessor alters the thermostat set points. This reduces the number of heating or cooling cycles per day, and reduces the number of actuations of the latching relays in the thermostat, conserving remaining battery life. At a further drop in battery voltage the set points are changed additionally. Additional functions, such as second level heat, second level cooling, and fan speed, are disabled. The change in heat or cooling cycles induces the occupant to check the thermostat where he or she will notice the LOW BATTERY message.

Abstract: A thermostat, of the type that employs latching relays to connect thermostat power to the various wires of the thermostat run, has a re-pulse feature that supplies latching pulses at a given interval, e.g., three hours, to ensure that the relays are in their proper state agreeing with the thermostat mode and the room temperature relative to the setpoint(s). In the case that the room air temperature is changing in a manner contrary to the current heating or cooling mode, which may indicate the latching relay has been knocked or bumped and needs to have its proper state re-established, the thermostat microprocessor issues pulses to the latching relay(s) more frequently, e.g., each 30 minutes, and the re-pulses may have a longer pulse width, e.g., increased from 20 ms to 25 ms.

Abstract: A user interface of a controller has multiple touch-sensitive input transducers, e.g., capacitive pads. The pads are dynamically indicated: When any given touch sensitive input device is needed for input at a given step of the programming operation, an associated light source illuminates that input device so it is visible to the user. Those touch-panel input devices not needed for that are left unilluminated, and the microprocessor ignores any input from those input devices. At each step of the operation or programming of the controller, only those input transducers for the inputs that are permitted or relevant to that state are indicated. Correspondingly, only the inputs that are generated by actuating the input transducers for the valid (i.e., permitted or relevant) inputs results in a change in the state of the program in the microprocessor.

Abstract: A furnace controller circuit includes a microprocessor with input ports and output ports including ports to issue control signals for actuation of inducer, gas burner, and furnace blower. A temperature-actuated limit switch commences a furnace shut-down sequence when the temperature of the furnace heat exchanger exceeds a predetermined limit temperature, and then resets to permit a turn-on sequence. An LED visible fault indicator is coupled to the microprocessor to provide visible fault messages. A non-volatile memory device coupled with the microprocessor is operative to store fault indications when present. In the event of power restoration after power failure, the limit switch status and other fault status are maintained. A lockout period is computed based on length of furnace run time until fault and recent fault history. Limit switch and other safety faults are recorded and these can be weighted and ranked based on age of each fault occurrence.

Abstract: In an electromechanical relay the core of the relay coil and a corresponding zone of the armature are each provided with a pole face of zig-zag or stair-step configuration. A succession of corresponding edges of the core and armature pole faces concentrate the magnetic flux to increase the initial force on the armature and to limit the closing force as the armature reaches the closed position. The armature bearing is shaped to create a longitudinal wipe motion. The relay exhibits faster and quieter action with less bounce and reduced contact chatter.

Abstract: A voltage or power conditioning and control device may be used in line with a source of AC line power and a reactive load such as a single-phase induction motor. The device operates to absorb some of the power reflected by the AC load and generate a synthetic power wave to supplement and correct the applied power in level and phase. The device employs a pair of power capacitors, and a pair of electronic switch devices each with a diode in parallel. Gating or command signals are generated based on the line voltage and timing, e.g., zero crossings. The phase or timing of the command signals is selected for a normal or no-boost mode, a voltage boost mode, or a voltage reduction mode. The capacitors are considered in series with the load, and improve the power factor to the load. A variation of this device may be used in conjunction with a solar array or other local power source.

Abstract: A motor start circuit for an AC induction motor employs a DC relay whose NC contacts are placed in series with the start capacitor. A half full-wave rectifier arrangement has an AC input connected to the junction of the relay switch and the start capacitor, and DC outputs applied across the relay actuator coil. In the event of intermittent application of power to the motor, any residual charge on the start capacitor will feed current to the actuator coil to hold the relay switch open until the residual charge has decayed sufficiently, to avoid damage to the motor from capacitive discharge. A high magnetic retentivity core can be used to hold the relay off for sufficient time for stored energy to dissipate.

Abstract: A motor start circuit for an AC induction motor employs a DC relay whose NC contacts are placed in series with the start capacitor. A half full-wave rectifier arrangement has an AC input connected to the junction of the relay switch and the start capacitor, and DC outputs applied across the relay actuator coil. In the event of intermittent application of power to the motor, any residual charge on the start capacitor will feed current to the actuator coil to hold the relay switch open until the residual charge has decayed sufficiently, to avoid damage to the motor from capacitive discharge. A high magnetic retentivity core can be used to hold the relay off for sufficient time for stored energy to dissipate.

Abstract: A power controller for applying power to an induction motor or similar AC load has a variable drive circuit for staring and switching a portion of the AC input line power. In one mode, the input line power is fed straight through to the load. In another mode, the AC waveform is reshaped to improve the power factor or to boost its RMS value, e.g., for brownout protection. In a further mode the output power can be provided at a different frequency from the input line power. Vector control increases efficiency through power optimization, with sensing of load requirements. Sensing of regeneration pulses at the commencement of a half cycle can be employed for direct sensing of motor speed or load.

Abstract: PWM AC power is supplied to an induction motor or other AC load. The frequency and magnitude of the waveforms is controlled by detecting the peak voltage or width of the reverse EMF pulses at the commencement of the power waveform applied to the load, and then adjusting the applied AC power based on the detected peak voltage or width. Alternatively, the depth of width of a notch that follows the reverse EMF pulse can be detected and used to control the applied AC power.