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 present invention discloses a system of energy-efficient and constant-pressure parallel-coupled fluid-transport machines, 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 parallel-coupled fluid-transport machines 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: In order to maintain normal states of machines during cutoff of electric power, an uninterruptible power supply (UPS) is required for a short time before a power generator starts to send out electric power. For normal functioning of a UPS, it is necessary to periodically detect the state of each battery thereof. In addition to measuring the variation of voltage and current of a battery by using a microprocessor, a sensor, and an analog-to-digital converter (ADC), the variation of voltage versus time (i.e., the voltage drop rate) of the battery during discharge is also measured. In other words, the voltage drop rate of a battery is measured as a standard for determining whether the battery is applicable to the UPS.

Abstract: A cooling tower for automatically adjusting flow rates of cooling water and cooling air with variations of a load comprises a plurality of thermometers; a hygrometer; at least one controllers; a cooling water pump; and at least one cooling towers connected in parallel. The desired data, such as optimum allowance operating range, heat transferring property of cooling towers, outer gas bulb temperature, approach and relations therebetween are calculated numerically and then are built in the controller. As the cooling tower is operated, by the measuring of the thermometer, messages are transferred to the controller, the practical data and predetermined data are compared in the controller so as to acquire an optimum cooling water flow and cooling air flow. Then, the controllers are used to control the cooling fan in the cooling pump and cooling towers. Thus, an optimum flow rate is acquired. Therefore, the power is saved. The flow rate of the present invention is changed with the load of the ice water mainframe.