| 摘要 |
The system includes a central fluid heater or cooler and an electrically driven centrifugal pump which pumps fluid therefrom to a supply main from which individual lines lead to each unit supplied. Return lines from each unit bring the used fluid back to the heater or cooler. The supply main is provided with a single digital flow meter or equivalent measuring device and digital thermometer. Each supply line has a control valve and means to signal the opening and closing of that valve. Each return line includes a digital thermometer. The signals from the above-mentioned apparatus are supplied to a microprocessor. The quantity of energy used by each unit is proportional to the volume of fluid received, which is metered by the change in flow when the unit valve is opened and the change in the opposite direction when the valve is closed, multiplied by the temperature difference between the received and the returned water. The microprocessor is multiplexed to monitor each unit in succession at short time intervals and make necessary calculations.
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