Abstract: A method for operating an air conditioner includes transmitting a plurality of signals between a remote user interface and the air conditioner through a plurality of wires that extend between the remote user interface and the air conditioner when the air conditioner is in a diagnostic mode. Each signal of the plurality of signals corresponds to a respective one of the plurality of wires. The method also include sequentially presenting a respective one or more characters on a display of a user interface of the air conditioner in response to each signal of the plurality of signals being received at the air conditioner.

Abstract: A water heater appliance, including methods of operation, is provided herein. The water heater appliance may include a casing, a tank, an inlet conduit, an electric heating system, and a controller coupled to an auxiliary power generator. The tank may be disposed within the casing and define an inlet and an outlet. The inlet conduit may be mounted to the tank at the inlet of the tank. The controller may be operably coupled to the electric heating system and configured to initiate a heating cycle. The heating cycle may include identifying a daily peak auxiliary power period, determining a contemporary voltage reading at the water heater appliance, predicting an occurrence of the daily peak auxiliary power period from the auxiliary power generator, and heating water within the water heater at the predicted occurrence of the daily peak auxiliary power period.

Abstract: A method for operating an air conditioner includes transmitting a plurality of signals between a remote user interface and the air conditioner through a plurality of wires that extend between the remote user interface and the air conditioner when the air conditioner is in a diagnostic mode. Each signal of the plurality of signals corresponds to a respective one of the plurality of wires. The method also include sequentially presenting a respective one or more characters on a display of a user interface of the air conditioner in response to each signal of the plurality of signals being received at the air conditioner.

Abstract: A method of operating a rolling piston rotary compressor includes obtaining an angular position and an angular speed of a rolling piston of the compressor, for example, using a tachometer or shaft encoder or observer. The method further includes obtaining an electromagnetic torque applied by an electric motor that is mechanically coupled to the rolling piston. The method further includes calculating a load torque exerted on the rolling piston based on these obtained values by using a load torque observer model that is formulated using known geometries of the compressor and thermodynamic models for the gas compression process. The operation of the electric motor is then adjusted such that the electromagnetic torque applied by the motor is equivalent to the calculated load torque such that noise and vibrations are minimized.

Abstract: A method of operating a synchronous motor includes using a rotor angle observer model to calculate an observed rotor angle and a speed estimator model to calculate an observed angular speed of the rotor. The observed rotor angle may be used to ensure that the stator magnetic field generated by the stator is oriented 90° ahead of the rotor magnetic field. The observed angular speed may be used to regulate the motor operation to achieve the desired speed.

Abstract: A method of operating a compressor includes obtaining a harmonic series representation of speed variation as the rotor rotates through each revolution. The method includes regulating an electric motor to compensate for or cancel out the periodic speed variation. Specifically, the method includes calculating an electromagnetic torque using a torque control input model based on the speed error and the harmonic series representation of the speed error. The operation of the electric motor is then adjusted such that the electromagnetic torque applied by the motor cancels out the speed variation such that noise and vibrations are minimized.

Abstract: Hot water heater systems including electronic mixing valves and methods for controlling such valves are provided. An electronic mixing valve provides a flow of water in a mixed output line. A method includes monitoring an input temperature of cold water supplied to the valve, storing a value of the input temperature, and setting a position limit of the valve based on the stored value, wherein the position limit of the valve is greater than a fully closed position of the valve and less than a fully open position of the valve.

Abstract: A method for defrosting a heat pump includes operating a fan at a particular speed. The fan is positioned to circulate air across the exterior coil of the heat pump. The method also includes measuring a power of the fan while the fan is operating at the particular speed and initiating a defrost of the exterior coil of the heat pump when the power of the fan is less than a threshold power.

Abstract: A water heater appliance and associated methods of operation are provided for regulating an output temperature of a mixing valve to a target temperature. The method includes determining the output temperature and an error value between the output temperature and the target temperature. A controller regulates the mixing valve according to a proportional-integral-derivative (PID) control algorithm for adjusting the output temperature to the predetermined target temperature. A proportional gain, an integral gain, and a derivative gain of the PID control algorithm vary according to a gain schedule depending on the error value between the output temperature and the predetermined target temperature.

Abstract: Hot water heater systems including electronic mixing valves and methods for controlling such valves are provided. An electronic mixing valve provides a flow of water in a mixed output line. A method includes monitoring an input temperature of cold water supplied to the valve, storing a value of the input temperature, and setting a position limit of the valve based on the stored value, wherein the position limit of the valve is greater than a fully closed position of the valve and less than a fully open position of the valve.

Abstract: A system and method of operating a water heater appliance provides an indication to a user that an excessive amount of hot water has been drawn from the hot water heater. The system includes a hot water heater, a mixing valve, a flow detector, and a controller configured for regulating the mixing valve to restrict the flow of hot water through the mixing valve when a predetermined amount of hot water has been withdrawn within a predetermined time period. By temporarily restricting the flow of hot water, a short duration of cold water will be provided to the user as an indication that an excessive amount of hot water is being used. In response, the user may reduce or terminate the use of further hot water, resulting in a reduced energy and water consumption.

Abstract: Air conditioner units and methods for determining indoor room temperatures are provided. A method includes calculating a difference between a first temperature received from a first temperature sensor and a second temperature received from a second temperature sensor. The first and second temperature sensors are disposed within an indoor portion of an air conditioner unit, the first temperature sensor disposed proximate an indoor heat exchanger of the air conditioner unit, the second temperature sensor spaced from the indoor heat exchanger relative to the first temperature sensor. The method further includes modifying the second temperature based on the difference to obtain a corrected temperature, and outputting the corrected temperature.

Abstract: A system and method for controlling a mobile repeater are provided. The method includes determining a signal level for each of a plurality communication sites adjacent the repeater. The method further includes assigning a communication frequency to the repeater based on the determined signal levels for the plurality of communication sites adjacent the repeater.

Abstract: An embodiment is a method for configuring a terminal (e.g., a radio) over a radio control channel. Instead of requiring on-site technicians to physically connect to the radios or error-prone and time consuming data calls to individual radios, an embodiment broadcasts software and configuration data as part of one or more radio control channel messages. As the radio control message or multiple messages are broadcast, any radio listening to the radio control message(s) may be configured. Additionally, radios of a particular type will be configured to use the same version of software and configuration data.

Abstract: A system and method for controlling a mobile repeater are provided. The method includes determining a signal level for each of a plurality communication sites adjacent the repeater. The method further includes assigning a communication frequency to the repeater based on the determined signal levels for the plurality of communication sites adjacent the repeater.

Abstract: An embodiment is a radio system including a primary radio site and one or more fully redundant hot standby radio sites that may be activated in the event of a catastrophic failure of the primary radio site. In an embodiment, a hot standby radio site may be activated automatically to substantially avoid the radio service restoration delay that would accompany, for example, manual initiation of the failover to the hot standby radio site.

Abstract: An embodiment is a method for configuring a terminal (e.g., a radio) over a radio control channel. Instead of requiring on-site technicians to physically connect to the radios or error-prone and time consuming data calls to individual radios, an embodiment broadcasts software and configuration data as part of one or more radio control channel messages. As the radio control message or multiple messages are broadcast, any radio listening to the radio control message(s) may be configured. Additionally, radios of a particular type will be configured to use the same version of software and configuration data.

Abstract: A cable-free programmable radio is described. In one exemplary implementation, a radio includes an infrared port configured to receive programmable information from a host device via an infrared signal. The radio also includes a control system having a selectable programmable mode to enable the radio to download the programmable information from the host device and configure the radio function in accordance with the programmable information. A radio may be configured/reconfigured (such as when “cloning” the radio) by connecting the radio to a host device through the infrared port, wirelessly.

Abstract: Method and processor for determining loading of a communications system shared by a plurality of user-terminals are provided. The method allows a respective terminal for monitoring a control channel including logical messages therein. The monitoring of the messages in the control channel is performed regardless of whether or not the logical messages therein are specifically addressed to that terminal. The method further allows for estimating a parameter indicative of system loading based on information in the monitored logical messages.

Abstract: In accordance with the present invention, the quality of a received digital signal is determined by the receiver, such as by observing the received signal strength indication (RSSI) and/or the bit error rate (BER). When the quality drops below a first threshold, the receiver injects white noise into the reproduced audio signal to simulate the noise that typically accompanies an analog wireless signal of low quality. The amount of injected white noise may be increased as the signal quality continues to decrease beyond the first threshold. Preferably, at a second threshold at which the receiver can no longer reassemble the received signal, the white noise is muted to audibly indicate to the user that the signal has been lost.