Abstract: A method for determining a set of optimal operating parameters for a pumping plant that pumps a fluid medium by a set of multiple pumps connected in parallel includes: determining, from the set of pumps, a set of possible scenarios, each scenario indicating, for each pump in the set, whether the pump is running or not running; optimizing, for each scenario, a set of operating parameters including operating parameters of the pumps that are running according to the respective scenario so that all running pumps together bring a given input mass flow of the medium from a given input pressure to a given output pressure while minimizing a total power consumption of all running pumps, and assigning the found minimum power consumption and the corresponding optimal operating parameters to the respective scenario; and determining, from the set of scenarios, the scenario with a lowest power consumption.

Abstract: A shift control method of a transmission including an electric oil pump (EOP) directly connected to a friction clutch for a vehicle may include: when a shift is initiated, setting, by a controller, a predetermined first target RPM for controlling the EOP; determining, by the controller, a target current based on the first target RPM; maintaining, by the controller, the first target RPM until an EOP driving current reaches the target current; when the EOP driving current is greater than or equal to the target current, linearly reducing, by the controller, an RPM of the EOP from a predetermined second target RPM to a third target RPM; and increasing, by the controller, an EOP driving power to increase a friction force of the friction clutch such that a slip of the friction clutch is smaller than a predetermined reference slip.

Abstract: A power electronics assembly that controls an electrically-actuated turbocharger includes a printed circuit board (PCB) having a non-conductive substrate supporting one or more electrical components that attach to the non-conductive substrate on one or more sides of the PCB; one or more conductive layers that couple with the non-conductive substrate and conduct electrical current within the PCB; a fluid barrier layer applied to an outer surface of the non-conductive substrate or conductor layer; and a PCB housing, configured to couple with the electrically-actuated turbocharger, having a fluid cavity that communicates liquid from an internal combustion engine (ICE) to the fluid barrier layer separating the liquid and the PCB.

Abstract: An in-room air conditioner adjustment method is provided and includes: obtaining a return air temperature detected by a temperature sensor corresponding to each air conditioner; adjusting, according to a difference between the obtained return air temperature and a temperature threshold, a fan rotational speed of each air conditioner until it is determined that an absolute value of the difference between the obtained return air temperature detected by the temperature sensor and the temperature threshold is less than a first specified value; determining that the absolute value of the difference between the return air temperature detected by the temperature sensor; and when an absolute value of a difference between fan rotational speeds of any two adjacent air conditioners is greater than a second specified value, adjusting a fan rotational speed of an air conditioner whose fan rotational speed is lower in the two adjacent air conditioners.

Abstract: A water pumping control device may include a primary power source and a secondary power source. The primary power source may be configured to provide a primary power input to a processing unit, and the secondary power source may be configured to provide a secondary power input to the processing unit. A primary pump and a secondary pump may be in communication with the processing unit, and the primary pump and the secondary pump may each be variable in speed. The primary pump and the secondary pump may each be in fluid communication with a sump so that when a pump is activated, the pump may remove water from the sump. A water level sensor may be in communication with the processing unit, and the water level sensor may be configured to provide a water level input describing a water level in the sump to the processing unit.

Abstract: An industrial fluid circulating system having at least one fluid circulation circuit, includes a plurality of pumps connected in parallel to circulate the fluid through each of the fluid circulation circuit, a separate motor driving each pump, a load detector to sense operating loads on the system and each circuit, and a speed control to vary the speed of each motor to thereby vary the pumping capacity of each pump in response to the detected load on the system, each pump of each respective circuit running simultaneously at a substantially similar speed or a predetermined equal reduced speed of the respective circuit or an almost equal reduced speed or a similar reduced speed.

Abstract: A fuel forwarding skid for delivering fuel from a storage area to a plurality of turbines includes at least two pumps for delivering fuel to a skid outlet line. A flow control device is connected to the pumps to control an output of the pumps. A recirculation line is in communication with the skid outlet line and is adapted to return a portion of the fuel in the skid outlet line to the storage area. A flow meter is in communication with the recirculation line to measure a rate of flow in the recirculation line, and the flow control device controls the output of at least one of the pumps in accordance with the rate of flow in the recirculation line.

Abstract: Disclosed are a mobile hydraulic generator having rapid response by scattering a small motor for generating a flow of fluid and a small pump, and a control method thereof. The mobile hydraulic generator includes: a flow generator including n pumps operated by n motors to generate an amount of a hydraulic fluid; a proportional hydraulic control valve to control output hydraulic pressure according to the amount of the hydraulic fluid; a pressure sensor to detect the output hydraulic pressure; and a hydraulic servo loop controller to which required hydraulic pressure and required amount of fluid are input by a user, to which feedback the output hydraulic pressure, to generate a pressure control signal for controlling the proportional hydraulic control valve based on the required hydraulic pressure and a change amount of the output hydraulic pressure and to generate an RPM input signal for controlling RPM of the n motors.

Abstract: A circulation pump assembly (1) includes an electric drive motor (6) and a control device (10, 12) for the control of the drive motor (6). The control device (12) includes a communication interface (13) designed for connection to at least one external sensor (38, 50, 52, 54, 56) and/or at least one further assembly (40, 42, 44, 46, 48, 58, 62, 64, 66, 68) to be controlled by the control device, as well as to a heating installation and/or air conditioning installation with such a circulation pump assembly (1).

Abstract: The present invention provides a liquid delivery device for liquid chromatographs which, by performing liquid delivery at an accurate flow rate with limited pulsation, gives accurate results of analysis. The present invention, with a view to preventing erroneous operation due to errors in measurements at the time of judgment of completion of compression of liquid, establishes the judgment point before the pressure measured by a cylinder pressure detector agrees with the pressure measured by a discharge pressure detector and also calculates the point of completion of compression. Control in this manner prevents pressure fluctuation. It also calculates for control the point of completion of compression from the history of compression performed previously.

Abstract: A water supply apparatus is capable of performing a backup operation, without lowering water supply capability, when a failure has occurred in one control substrate due to surge or noise caused by lightning or sensor wear, by switching to the other control substrate, and capable of reliably performing the backup operation. The water supply apparatus includes: a plurality of pumps; a plurality of inverters each configured to change and control a rotational frequency of a corresponding one of the plurality of pumps; and a plurality of control substrates configured to control the plurality of inverters. When an abnormality occurs in one control substrate, other control substrate backs up the one control substrate to thereby allow the water supply apparatus to continue its operations. The one control substrate, the plurality of inverters, and the other control substrate are connected in series by communication lines.

Abstract: The present pump devices provide a dual pump using two (or more) electric motors (e.g. brushless DC motors) driving the pumps independently, including integration of hydraulic and electrical components and connectors. The illustrated arrangements include an in-line single shaft version, a parallel separate shaft version, and an inside-outside version. Each configuration includes a housing supporting formation of: shared structural support for the pumps and motors (e.g., bearings, stator, relationship of components), fluid pump and hydraulic system (e.g., fluid passageways, ports connectors) and motor electrical control (e.g., control circuitry and sensory components).

Abstract: The proportioner (10) has a variable speed controlled DC motor (12) having a gearbox (14) and crankshaft (16) at either end which are connected to reciprocating piston pumps (18). The outputs (18a) of the two pumps (18) are fed to a manifold (22) where the pressure of each output is measured. The user sets a setpoint pressure (e.g. 1000 psi) and the controller (26) then compares the pressures of the two components and controls the higher of the two relative to the setpoint. Ratio assurance is monitored by continuing to look at both output pressures. If one side falls below a predetermined percentage of the setpoint (50% in the preferred embodiment), an alarm may be raised or operation stopped.

Abstract: The invention concerns a method and device for controlling a number of infusion pumps 2-10, whereby each infusion pump (2-10) has an infusate assigned to it which is administered within a pre-determinable period of time assigned to it as an infusion at a pre-determinable infusion rate to a living being, whereby the infusion pumps (2-10) exchange control data for activating and deactivating the various infusions in a chronologically coordinated manner autonomously.

Abstract: The invention relates to a method of realizing a vacuum in a vacuum chamber. The vacuum chamber is connected to a pumping system shared by a plurality of vacuum chambers. The method includes separately pumping down each vacuum chamber. The invention further relates to n arrangement of a plurality of vacuum chambers connected to a pumping system. In this arrangement, the pumping system is arranged for pumping down each vacuum chamber separately.

Abstract: The present invention provides a new and unique method and apparatus for operating and running multiple pumps in a system together at a substantially synchronous torque to achieve a desired setpoint. Each of the multiple pumps may be operated with a variable speed drive. The present invention may also take the form of the system having the multiple pumps with a system controller for operating and running the multiple pumps, a pump for operating and running in such a system, a system control module for such a system controller, as well as a pump control module for running and operating such a pump.

Abstract: An object of the present invention is to provide a reactor feedwater pump control system, wherein when a condensate pump is tripped, the decrease in feedwater flow of feedwater supplied to a steam generator is minimized to suppress the decrease in water level of the steam generator, and at the same time preventing operating condensate pumps from continuing a run out operation. The feedwater pump control system is provided with a feedwater supply system, which includes a plurality of condensate pumps disposed in parallel for boosting condensate water from a condenser; a plurality of reactor feedwater pumps disposed in parallel for further boosting and supplying the condensate water to a steam generator; and variable frequency power supply systems each for driving an electric motor of the reactor feedwater pump at an adjustable speed.

Abstract: The present invention relates to an oil pump control apparatus of a hybrid vehicle that controls an oil pump according to a demand of an output torque and oil temperature, and a method thereof. A oil pump control method includes controlling hydraulic line pressure by operating a oil pump at a maximum power if a starting demand for a hybrid vehicle is detected, calculating a viscosity to correspond to an oil temperature in an engine stop mode and controlling a rotation speed of the oil pump at a low power, and calculating a viscosity according to a variation of a line pressure in a driving mode and controlling the rotation speed of the electric oil pump in either a low power, a middle power, and a high power state.

Abstract: A refrigerant system (10, 100, 200) is provided with a power control system (30, 130, 230). The power control system adjusts the speed of the motors driving the refrigerant system components such as a compressor, a fan or a pump via a variable speed device (75, 175, 275) or bypasses the variable speed device (75, 175, 275) for normal operating speeds. A single power control system may be provided for the entire refrigerant system or each component may be independently controlled.

Abstract: A method of pressure control for transmissions having a hydraulic circuit selectively communicating with first and second pumps via first and second regulators includes commanding communication to the hydraulic circuit to transition from the first to the second pump and the PCS to set the regulators to a high pressure-regulation level. The hydraulic circuit line pressure is raised to an elevated value exceeding a target value. The line pressure is lowered from the elevated to the target value at or after completing the transition to the second pump. The method may include transitioning communication with the hydraulic circuit from the second to the first pump. The PCS maintains the regulators at the high level and line pressure is raised to the elevated value. PCS sets the regulators to a low level, and line pressure returns to the target only at or after completing the transition to the first pump.

Abstract: A control and instrumentation system utilizes a subsea data hub to establish closed loop of between subsea production system components and a surface located controller. The control and instrumentation system can be utilize to operational control all of the required process components of the subsea production system from the surface located controller.

Abstract: Method for adjusting a compressed air installation using several electrically driven compressors of what is called the “loaded/unloaded” type and/or the turbo compressor type and/or the compressor type with variable rotational speed, wherein these compressors are each connected to a single compressed air network with their outlets, and wherein use is made of a control box which makes it possible to adjust the pressure in the compressed air network around a target pressure to be set. The adjustment takes place by controlling the flow of one or several of the compressors, in particular in order to increase the overall flow supplied by the compressors when the pressure drops too much, and in order to lower the overall supplied flow when the pressure becomes too high.

Abstract: Method for controlling one or more vacuum generators (1) and thereby the vacuum in a vacuum sewage system, in particular controlling one or more liquid ring screw pumps in such system, including beyond the generator/s (1) one or more tubular collectors or suction pipelines (2) connected to the vacuum generator and one or more toilets, urinals, grey water sinks etc (3, 4), connected to the suction pipeline through branch pipelines (6). The rotational speed of the vacuum generator (1) is controlled on the basis of the set vacuum requirement.

Abstract: The invention relates to a device for calculating blood flow and to an apparatus for extracorporeal blood treatment provided with the device. The device includes a memory for receiving and storing either a first datum relating to a blood flow removed from the patient Qb, or a second datum relating to a flow of liquid Qt crossing a tract of the extracorporeal circuit, and a third datum relating to a flow of infusion liquid Qinf flowing through the infusion line. The device also comprises a control unit able to calculate the first datum or the second datum as a function of the third datum relating to the flow of infusion liquid Qinf.

Abstract: An air conditioner having two compressors enables, when one compressor is started, the phase advance capacitor for the other compressor to be temporarily separated and used in parallel with the phase advance capacitor for the one compressor. These compressors can have an increased starting torque without using a starting capacitor.

Abstract: The present invention provides a liquid delivery device for liquid chromatographs which, by performing liquid delivery at an accurate flow rate with limited pulsation, gives accurate results of analyses. The present invention, with a view to preventing erroneous operation due to errors in measurements at the time of judgment of completion of compression of liquid, establishes the judgment point before the pressure measured by a cylinder pressure detector agrees with the pressure measured by a discharge pressure detector and also calculates the point of completion of compression. Control in this manner prevents pressure fluctuation. It also calculates for control the point of completion of compression from the history of compression performed previously.

Abstract: An air-compressing apparatus has four compressors individually supplying compressed air to a tank having a pressure sensor. The pressure sensor is connected to control circuits of the compressors. The control circuits compute times needed for the tank pressure to reach minimum and maximum pressures, respectively, of the tank by using the detected tank pressure and also using a tank pressure change value. The computed time values correspond to the consumption of compressed air. Thus, the control circuits can control the number of compressors to be operated according to the consumption of compressed air.

Abstract: A supply flow path for supplying a solvent is described. The supply flow path includes metering devices each with a piston, the metering devices being adapted for metering the solvent through separate source paths feeding the supply flow path. The supply flow path further includes a control unit adapted for controlling the metering devices' piston movement in accordance with solvent pressure, wherein a variation of the solvent pressure gives rise to a corresponding variation of a solvent volume contained in the supply flow path or a part thereof. The control unit is adapted for compensating for the variation of the solvent volume by corresponding movements or forward or backward displacements of the pistons.

Abstract: The invention concerns an installation for high pressure compression with several stages, normally used for producing PET bottles. The inventive installation comprises a main pipe (2) emerging in a baffle plate (3), wherein at least two compressors (4, 5) are mounted in series each having its own drive member (9, 10). The installation is equipped with means (7) for determining the pressure at the output of the main pipe (2), said installation being connected to a control box (8). Typically, the control box (8) is connected to at least two of the drive members (9, 10) of the compressors (4, 5) and ensures monitoring of said compressors such that the latter rotate jointly whether charged or uncharged. Thus, the compressors (4, 5) are jointly charged based on the pressure prevailing in the baffle plate (3), such that the charging of the compressor representing the overpressure stage, the compressor(s) of the lower compression stages are automatically and jointly charged.

Abstract: A method for optimizing the operation of several compressor units in a natural gas compression station. After a second or further compressor unit is started, the speeds of the running compressor units are set according to a fixed speed ratio in relation to characteristic data established for each compressor unit. The fixed speed ratio is altered by adjusting the rate of flow to the same percentage via the speed of rotation until the preventive pump valves of the gas compressor station are closed, whereupon the operating points of the compressor units are guided, where possible, in the characteristic data thereof, to the maximum efficiency. The optimum set speed values are determined according to continuous operating characteristics of the gas compression station by coordinated variation of the set speeds of the compressors, taking into account fuel consumption of the gas compression station. The stored fixed speed ratio is adjusted according to the optimum set speed values thus determined and stored.

Abstract: In accordance with some embodiments, a pumping station controller (14) is provided for monitoring pumping station hardware such as a well level sensor (8) and pumps (10a, . . . , 10n). A user interface (12) enables a user to input data to the controller (14) for controlling the operation of the pumps (10) based on the sensed liquid level. Pumping hardware configurations vary from site to site so that wiring the hardware to the controller may be confusing for the user. To address this problem the controller may comprise a software product (20). The software product may comprise instructions for processor (19) to determine a suitable wiring configuration between the controller (14) and the pumping station hardware, based upon user entered parameters identifying the pumping station hardware to be used.

Abstract: The present invention discloses a system of energy-efficient and constant-pressure fluid-transport machines coupled in parallel, which can flexibly and massively provide gas and water to every fabrication unit. The system of the present invention comprises: variable-frequency centrifugal fluid-transport machines, pressure gauges, power meters, flow meters, and controllers. The performance curves of the abovementioned system of fluid-transport machines coupled in parallel and the system impedance curves of the loads are analyzed theoretically and built in the controllers together with the equal-efficiency curves provided by the manufacturer. When the system is operating, the data detected by the pressure gauges, power meters, and flow meters are compared with the built-in data to obtain the optimal energy-efficient conditions as the operational criteria of the system of the present invention.

Abstract: The application device for liquid containing micro-nano bubbles generates micro-nano bubbles in a wide size distribution with use of a submerged pump-type micro-nano bubble generator and a spiral flow-type micro-nano bubble generator. A micro-nano bubble generating aid metering pump is controlled by a bubble level meter and a level controller, so that the supply amount of a micro-nano bubble generating aid is controlled in response to the level of bubbles from a fluid level. The supply amount of a micro-nano bubble generating aid is also controlled by a turbidimeter and a controller in response to the turbidity of the liquid in a micro-nano bubble generation tank, while the amount of air supplied to the submerged pump-type micro-nano bubble generator is controlled in response to the turbidity of the liquid. Therefore, the device can produce a large amount of various micro-nano bubbles in a wide size distribution more economically.

Abstract: A system for maintaining at least one air characteristic in an air ventilated facility using at least one fan filter unit, the system comprising at least one sensor for sensing the at least one air characteristic, the at least one sensor being exposed to the air ventilated facility; the at least one sensor being operatively connected to a control system that is operatively connected to the at least one fan filter unit; the control system receiving output readings from the at least one sensor and determining if the output reading is within a range and, in response to a negative determination, providing a command to the at least one fan filter unit to adjust the at least one fan filter unit operating speed. A corresponding method and apparatus are also disclosed.

Abstract: The method of managing time M, at which maintenance of a gas compressor multiple system incorporating therein a plurality of gas compressors should be carried out, involves making a comparison between a value of M and a predetermined time N for necessary maintenance to carry out the maintenance when the value of M is larger than or substantially equal to a value of N, where M is equal to the product of the operating time T of the system, the average load factor L, and a safety factor C.

Abstract: A sump liner comprising a liner wall joined with a base member, the liner wall extending about the periphery of the base member, the liner wall comprising a primary reservoir portion and a secondary reservoir portion, with a weir extending from the base member and the inside surface of the liner wall. The weir divides the sump liner interior into a primary reservoir and a secondary reservoir, with a primary pump to remove water from the primary reservoir and a secondary pump to remove water from the secondary reservoir. The primary reservoir receives drainage water through an inlet pipe. The secondary reservoir receives drainage water that flows over the weir in the event the primary pump in the primary reservoir fails, in which case the secondary pump in the secondary reservoir pumps out the water. The weir may have an inverted V-shape. A sump liner and with a vented lid bolted to it to form an airtight seal.

Abstract: An air conditioning system 1 includes a primary compressor (an engine-driven compressor 6) driven by a primary driving source (an engine 2) and a secondary compressor (a motor-driven compressor 7) driven by a secondary driving source (a motor 3). When a required cooling capability is equal to or greater than a predetermined value, the air conditioning system 1 causes the primary compressor (the engine-driven compressor 6) to be driven by the primary driving source (the engine 2) and adjusts the rotational speed of the secondary compressor (the motor-driven compressor 7), whereas when the required cooling capability is equal to or smaller than the predetermined value, the air conditioning system 1 causes the secondary compressor (the motor-driven compressor 7) to be driven by the secondary driving source (the motor 3) so as to control the rotational speed of the primary compressor (the engine-driven compressor 6).

Abstract: Disclosed are an air conditioning system with two compressors and a method for operating the same, so as to variably change a compression capacity of a refrigerant according to the variation of cooling load. Herein, when a full operation order is inputted to the two compressors in order to satisfy increased cooling load, the first compressor is first operated, and then the second compressor having a compression capacity of a refrigerant smaller than that of the first compressor is additionally operated, so that a current peak value for operating the compressors does not exceed an allowable current range of a circuit breaker installed in a home or building, thereby safely controlling the air conditioning system and simultaneously allowing the current to be provided to other electric appliances, thus improving users' convenience.

Abstract: A sump liner comprising a liner wall joined with a base member, the liner wall extending about the periphery of the base member, the liner wall comprising a primary reservoir portion and a secondary reservoir portion, with a weir extending from the base member and the inside surface of the liner wall. The weir divides the sump liner interior into a primary reservoir and a secondary reservoir, with a primary pump to remove water from the primary reservoir and a secondary pump to remove water from the secondary reservoir. The primary reservoir receives drainage water through an inlet pipe. The secondary reservoir receives drainage water that flows over the weir in the event the primary pump in the primary reservoir fails, in which case the secondary pump in the secondary reservoir pumps out the water.

Abstract: The present invention provides a fan installation for a cooling system of a motor vehicle, comprising at least two fans which respectively have an electric fan motor arranged in a separate housing and a fan wheel which can be driven by the fan motor. The fan installation also comprises a control unit for operating the fan motors. The invention provides for an improved fan installation with a simple and cost-effective design, which is achieved by arranging the control unit in the housing of one of the fans for operating both fan motors.

Abstract: A modular system for the control of at least one compression system for the compression a fluid medium, said compression system comprising compressors (C1-C7) and their controllers (A1-A7) for the compression of the fluid medium, secondary treatment devices for the treatment of the medium delivered from the compressors, and piping systems (17-19, 23) for conducting the fluid medium to a place of consumption (16, 22), said control system comprising a control unit (3) containing a data processing system (34) for controlling the compression system, a user interface (35) including a display associated with it and transmission means for the transmission of control data between the control unit, the controllers and pressure sensors. The transmission means consist of data communication buses, preferably serial communication buses (30-32) and a data communication port unit (33) serving to connect the bus to the control unit (34). The controllers and pressure sensors are connected to common data communication buses.

Abstract: Reactive fluids that react upon contact and are intended to be combined only at a site of application that is remote or not easily accessible are transported to the site by separate crescent internal gear pumps whose pump rates are governed by a control loop that uses individual mass flow rates and a common automatic controller. In preferred embodiments, a multi-lumen cable is used to convey the pump outputs individually to the application site, and an application head at the distal end of the cable both combines the individual flows and dispenses them to the site. The invention is useful for a variety of reactive systems and applications, but particularly for applying two-component epoxy linings to underground pipes.

Abstract: A method and apparatus are provided for continuously dispensing precise quantities of a liquid from a dispenser holding tank into a receiving tank. A first elastic tube permits fluid flow between the holding tank and the receiving tank and a first peristaltic pump controls the flow rate of liquid through the first elastic tube. A second elastic tube permits fluid flow between the holding tank and the receiving tank and a second peristaltic pump controls the flow rate of liquid through the second elastic tube. The flow rates through the first and second elastic tubes are independently controlled. The flow rate through the first elastic tube is maintained generally constant and at a substantially greater rate than the flow rate of the second elastic tube. The flow rate in the second elastic tube is varied to maintain a desired total flow rate into the receiving tank.

Abstract: A controller for managing a plurality of compressors in an efficient manner such that the system uses less energy, has lower maintenance cost and experiences less wear. For a system with multiple compressors the controller has the minimum number of compressors needed to maintain the pressure on at any given time and has no more than one compressor running in an unloaded condition for maximum efficiency. The system can quickly pressure up or down in conjunction with the needs of the system. The controller rotates the order of use of the compressors to spread the time of use and for limiting the number of times during an hour that each compressor can be turned on such that the compressors take turns running and turning on and off for even wear. The system seldom uses more than one compressor unloaded at any time.

Abstract: A sewage system comprising a network of sewage sumps that temporarily store sewage produced in a dwelling or other structure, each of said sumps preferably comprising a computer controller for operating a pump in the sump such that the sewage collected in the sump may be pumped out of the sump and into the collection system in a controlled manner to regulate the flow of sewage material in the system. The regulation of the sewage flow permits the efficient operation of a sewage treatment facility that receives sewage from the network of sewage sumps by insulating the facility from the peak burdens that would be placed on it at certain times of day in the absence of a system that regulates sewage flow into the system at the source of the sewage.

Abstract: An apparatus and method for providing redundant power and redundant fan speed control to a plurality of fans is provided. A first power supply input is electrically connected to a second power supply input to provide a combined power supply input. First and second fan speed controllers each having an input and an output are provided, along with first and second power converters each having an input and an output. The combined power supply input is electrically connected to the input of the first fan speed controller and the input of the first power converter. The combined power supply input is also electrically connected to the input of the second fan speed controller and the input of the second power converter. The output of the first fan speed controller is electrically combined with the output of the second fan speed controller to provide a combined fan speed control signal. The combined fan speed control signal is electrically connected to the plurality of fans.

Abstract: A water distributing installation controller includes water pumps for supplying clear water from a filtration plant to a distributing reservoir, a level gauge for measuring the water level of the distributing reservoir, a first flow meter for measuring the water supply directed thereto, a second flow meter for measuring the water delivery directed to a distributing area, a pumps-number control part for controlling the number of pumps operated, and a short-term demand prediction part for providing short-term demand prediction data on the water delivery to the pumps-number control part at the request thereof.

Abstract: A process for controlling a system for generating electricity which contains at least two compressors and two microturbines. Compressed gas from a pressure vessel is supplied to the first microturbine, and thereafter the pressure within the pressure vessel is measured. If the pressure is below a specified value, a first compressor is caused to operate to feed compressed gas to the pressure vessel. Thereafter, as the system needs require, a second compressor and, optionally, a third compressor is caused to furnish compressed gas to the pressure vessel. If the system pressure within the pressure vessel is too high, the third compressor is shut down and, if necessary, the second compressor and the first compressor are then sequentially shut down.

Abstract: A redundant, modular pump system includes a plurality of substantially identical pump modules. Each module includes constant speed drive circuitry, variable speed drive circuitry and a pump. Expansion is accomplished by adding modules. Reliability is enhanced by being able to operate each pump at constant or variable speed irrespective of whether other modules are being operated at different variable or constant speeds. A common, software driven control element activates drives and other devices in the modules to provide fluid on demand at a pre-selected pressure.

Abstract: The invention is a system and process for pumping fluids in lines, comprising using, on the lines, a pump with at least two alternating fluid pumping units. Each pumping unit (PU1, PU2) comprises a cylinder (2) and a piston (1) alternately displaceable in the cylinder under the action of a power source (M), under the control of a control device (PC), with, for both pistons, imposed displacement functions (f(t), g(t)) suitably phase-shifted in relation to one another so as to obtain a first operating mode corresponding to substantially constant delivery rate. This pump is operated in the same circuit according to the complementary second operating mode corresponding to a substantially constant intake rate by inversion of the direction of displacement of the pistons so as to apply to the pistons displacement functions (−f(t), −g(t)) symmetrical to those corresponding to the first operating mode.