Abstract: This disclosure includes methods for testing hydraulically-actuated devices and related systems. Some hydraulically-actuated devices have a housing defining an interior volume and a piston disposed within the interior volume and dividing the interior volume into a first chamber and a second chamber, where the piston is movable relative to the housing between a maximum first position and a maximum second position in response to pressure differentials between the first and second chambers. Some methods include: (1) moving the piston to the first position by varying pressure within at least one of the first and second chambers such that pressure within the second chamber is higher than pressure within the first chamber; and (2) while the piston remains in the first position: (a) reducing pressure within the second chamber and/or increasing pressure within the first chamber; and (b) increasing pressure within the second chamber and/or decreasing pressure within the first chamber.

Abstract: This disclosure includes methods for testing hydraulically-actuated devices and related systems. Some hydraulically-actuated devices have a housing defining an interior volume and a piston disposed within the interior volume and dividing the interior volume into a first chamber and a second chamber, where the piston is movable relative to the housing between a maximum first position and a maximum second position in response to pressure differentials between the first and second chambers. Some methods include: (1) moving the piston to the first position by varying pressure within at least one of the first and second chambers such that pressure within the second chamber is higher than pressure within the first chamber; and (2) while the piston remains in the first position: (a) reducing pressure within the second chamber and/or increasing pressure within the first chamber; and (b) increasing pressure within the second chamber and/or decreasing pressure within the first chamber.

Abstract: This disclosure includes methods for testing hydraulically-actuated devices and related systems. Some hydraulically-actuated devices have a housing defining an interior volume and a piston disposed within the interior volume and dividing the interior volume into a first chamber and a second chamber, where the piston is movable relative to the housing between a maximum first position and a maximum second position in response to pressure differentials between the first and second chambers. Some methods include: (1) moving the piston to the first position by varying pressure within at least one of the first and second chambers such that pressure within the second chamber is higher than pressure within the first chamber; and (2) while the piston remains in the first position: (a) reducing pressure within the second chamber and/or increasing pressure within the first chamber; and (b) increasing pressure within the second chamber and/or decreasing pressure within the first chamber.

Abstract: This disclosure includes methods for testing hydraulically-actuated devices and related systems. Some hydraulically-actuated devices have a housing defining an interior volume and a piston disposed within the interior volume and dividing the interior volume into a first chamber and a second chamber, where the piston is movable relative to the housing between a maximum first position and a maximum second position in response to pressure differentials between the first and second chambers. Some methods include: (1) moving the piston to the first position by varying pressure within at least one of the first and second chambers such that pressure within the second chamber is higher than pressure within the first chamber; and (2) while the piston remains in the first position: (a) reducing pressure within the second chamber and/or increasing pressure within the first chamber; and (b) increasing pressure within the second chamber and/or decreasing pressure within the first chamber.

Abstract: A disturbance, for example, a frequency variation, is generated in at least a portion of the power distribution network. The disturbance may be generated, for example, by an uninterruptible power supply (UPS) or some other component of the power distribution network, such as a switch. At least one node of the network experiencing the disturbance is identified and a topology of the power distribution network is determined responsive to identifying the at least one node. The at least one node may be identified by detecting a voltage-related artifact corresponding to the disturbance. A phase-locked loop (PLL)—based circuit may be used for fast artifact detection. Groups of devices in the network may be identified from the artifacts, and combinatorial optimization techniques may be used to determine connectivity within such groups.

Abstract: Some embodiments of the inventive subject matter provide a power distribution system for a data processing system. The power distribution system includes a plurality of uninterruptible power supply (UPS) units, respective ones of which are configured to be coupled to respective loads via respective load busses, at least one reserve bus, a switching circuit configured to selectively couple and decouple the UPS units and the load busses to and from the at least one reserve bus and a control circuit configured to control the switching circuit responsive to a state of the data processing system. The control circuit may be configured to cause the switching circuit to couple the first UPS unit to the at least one reserve bus concurrent with the first UPS unit being coupled to a first load via a first load bus.

Abstract: A disturbance, for example, a frequency variation, is generated in at least a portion of the power distribution network. The disturbance may be generated, for example, by an uninterruptible power supply (UPS) or some other component of the power distribution network, such as a switch. At least one node of the network experiencing the disturbance is identified and a topology of the power distribution network is determined responsive to identifying the at least one node. The at least one node may be identified by detecting a voltage-related artifact corresponding to the disturbance. A phase-locked loop (PLL)—based circuit may be used for fast artifact detection. Groups of devices in the network may be identified from the artifacts, and combinatorial optimization techniques may be used to determine connectivity within such groups.

Abstract: Some embodiments of the inventive subject matter provide a power distribution system for a data processing system. The power distribution system includes a plurality of uninterruptible power supply (UPS) units, respective ones of which are configured to be coupled to respective loads via respective load busses, at least one reserve bus, a switching circuit configured to selectively couple and decouple the UPS units and the load busses to and from the at least one reserve bus and a control circuit configured to control the switching circuit responsive to a state of the data processing system. The control circuit may be configured to cause the switching circuit to couple the first UPS unit to the at least one reserve bus concurrent with the first UPS unit being coupled to a first load via a first load bus.

Abstract: A sensor communications distribution system for a data center or other distributed electronic installation includes a plurality of communications distribution units mounted in a plurality of equipment racks. Each of the communications distribution units comprising a frame configured to be mounted in an equipment rack, a power bus supported by the frame and coupled to a power distribution network and a power line carrier communications interface circuit coupled to the power bus and to a plurality of external sensors (e.g., via connectors and/or wirelessly). Power may be provided to the sensors and/or to equipment in the racks from the communications distribution units.