Abstract: Electric power devices and control methods are provided which automatically select a line voltage or phase voltage of an AC voltage supply. The electric power device includes a switchable circuit, a sensor and a switch control. The switchable circuit connects to the AC voltage supply, and includes multiple switchable elements. The sensor ascertains a voltage level of the AC voltage supply, and the switch control automatically establishes a configuration of the switchable circuit through control of the multiple switchable elements. The switch control couples the electric power device in a line-line (delta) configuration to the AC voltage supply when the voltage level is in a first voltage range, and a line-neutral (wye) configuration when the voltage level is in a second voltage range.

Abstract: Apparatus and method are provided for facilitating air cooling of an electronics rack. The apparatus includes a tile assembly, temperature sensor and controller. The tile assembly is disposed adjacent to the electronics rack, and includes a perforated tile and one or more controllable air-moving devices associated with the perforated tile for moving air through the perforated tile. The temperature sensor is positioned for sensing air temperature adjacent and external to, or within, the electronics rack, and the controller is coupled to the tile assembly and the temperature sensor for controlling operation of the air-moving device. Airflow through the tile assembly is adjusted based on air temperature sensed, thereby facilitating air cooling of the electronics rack. In one embodiment, the tile assembly is a floor tile assembly with an air-to-liquid heat exchanger disposed between the perforated tile and the air-moving device for cooling air passing through the floor tile assembly.

Abstract: An electromechanical assembly is provided controlled by voltage across a motor or with an electronic system. The electromechanical assembly includes a control circuit coupled to sense voltage at the motor or within the electronic system, and an electromechanical actuator energized by the voltage sensed by the control circuit. A movable element is movable by the electromechanical actuator from an operational position to a quiesced position when the voltage sensed by the control circuit falls below a quiesced threshold. In certain embodiments, the voltage being sensed is across a motor of an air-moving assembly, which resides within a support structure, or the voltage being sensed is within the electronic system, which resides within the support structure, and the movable element is an interlock element which interlocks to the support structure to prevent removal of one or more components from the structure when sensed voltage is above the quiesced threshold.

Abstract: An electromechanical assembly is provided controlled by voltage across a motor or with an electronic system. The electromechanical assembly includes a control circuit coupled to sense voltage at the motor or within the electronic system, and an electromechanical actuator energized by the voltage sensed by the control circuit. A movable element is movable by the electromechanical actuator from an operational position to a quiesced position when the voltage sensed by the control circuit falls below a quiesced threshold. In certain embodiments, the voltage being sensed is across a motor of an air-moving assembly, which resides within a support structure, or the voltage being sensed is within the electronic system, which resides within the support structure, and the movable element is an interlock element which interlocks to the support structure to prevent removal of one or more components from the structure when sensed voltage is above the quiesced threshold.

Abstract: An environmental conditioning system for a computer room includes a perforated tile, a heat exchanger mounted to the perforated tile, and a forced air system mounted to the heat exchanger. The forced air system being configured and disposed to direct a flow of air having a first temperature into the heat exchanger. The flow of air exits the heat exchanger at a second temperature and passes through the perforated tile into the computer room. The second temperature is distinct from the first temperature.

Abstract: Automated control is provided of rotational velocity of an air-moving device cooling an electronics subsystem of an electronics rack. The automated control includes: automatically responding to a failure event associated with the electronics subsystem of the rack by setting rotational velocity of the air-moving device to a first upper limit (RPM1) above a normal operating limit; sensing motor temperature of a motor of the air-moving device; automatically increasing rotational velocity of the air-moving device to a second upper limit (RPM2) if the sensed motor temperature is below a first predefined temperature threshold (T1), wherein RPM2>RPM 1; maintaining rotational velocity of the air-moving device at the second upper limit while the sensed motor temperature is below a second predefined temperature threshold (T2), wherein T2>T1; and returning to normal operating rotational velocity of the air-moving device subsequent to servicing of the electronics rack responsive to the event.

Abstract: Automated control is provided of rotational velocity of an air-moving device cooling an electronics subsystem of an electronics rack. The automated control includes: automatically responding to a failure event associated with the electronics subsystem of the rack by setting rotational velocity of the air-moving device to a first upper limit (RPM1) above a normal operating limit; sensing motor temperature of a motor of the air-moving device; automatically increasing rotational velocity of the air-moving device to a second upper limit (RPM2) if the sensed motor temperature is below a first predefined temperature threshold (T1), wherein RPM2>RPM 1; maintaining rotational velocity of the air-moving device at the second upper limit while the sensed motor temperature is below a second predefined temperature threshold (T2), wherein T2>T1; and returning to normal operating rotational velocity of the air-moving device subsequent to servicing of the electronics rack responsive to the event.

Abstract: Apparatus and method are provided for facilitating air cooling of an electronics rack. The apparatus includes a tile assembly, temperature sensor and controller. The tile assembly is disposed adjacent to the electronics rack, and includes a perforated tile and one or more controllable air-moving devices associated with the perforated tile for moving air through the perforated tile. The temperature sensor is positioned for sensing air temperature adjacent and external to, or within, the electronics rack, and the controller is coupled to the tile assembly and the temperature sensor for controlling operation of the air-moving device. Airflow through the tile assembly is adjusted based on air temperature sensed, thereby facilitating air cooling of the electronics rack. In one embodiment, the tile assembly is a floor tile assembly with an air-to-liquid heat exchanger disposed between the perforated tile and the air-moving device for cooling air passing through the floor tile assembly.

Abstract: In a delta-connected power supply system, phase switching circuits are employed and are activated during the failure of one of N+1 converter units. This activation is employed even though there has been no outage in any one of the input phases. The result is two operating converters running in effect as three-phase converters. Since each of the converters then acts as a full wave three-phase bridge with a resistor load, the line currents are perfectly balanced although unity power factor is not maintained during this non-normal mode of operation. In such circumstances, higher power factor is temporarily sacrificed to achieve continuous operation and therefore higher overall system reliability.

Abstract: Disclosed is a circuit for preventing damage to a controllable switching circuit as a result of a reverse recovery current originating from a rectifier circuit coupled to the controllable switching element during recovery of the rectifier circuit. The damage prevention circuit includes a reactive impedance circuit coupled in parallel with the rectifier circuit for controlling a reverse recovery current from the rectifier circuit during recovery of the rectifier circuit. A second controllable switching element is employed to direct the reverse recovery current to the reactive impedance circuit in response to recovery of the rectifier. The second controllable switch also directs the reverse recovery current from the reactive impedance circuit to a load, wherein the reverse recovery current may be safely diminished.

Abstract: An electromagnetic contactor assembly with a sensing circuit for determining contactor state based upon the reluctance of the contactor coil. The coil has an electromagnetic coil and a movable contact separated from the coil by a gap when the coil is not energized. Energizing the coil causes the movable contact to close the gap and contact the coil. The determination of the relationship between the reluctance in the coil when the gap is in an open and closed state allows contactor gap status to be measured by measuring the coil inductance. A sensing circuit is added to the drive circuit to measure changes in AC current during the pulse cycle which holds the contacts in this closed position. The sensing circuit measures the AC current and is able to signal contactor status based on that value.