Due to the ever-increasing energy cost, the effective use of electricity in a building or factory has been increasingly significant issue. If we are able to construct the most suitable control system in the operational equipment built in a building, everyday energy-saving will be very easy to reach. In such a control system, there should be adequate temperature modulation, pressure adaptation in the water pipe, upload/download distribution of water chiller, monitoring of electricity consumption and database management.

In terms of the control of temperature and water pressure, the control system Delta currently presents includes AC motor drive with an analog-input temperature controller to achieve modulation by PID operation. Our new VFD-EL series AC motor drive is built-in with smart PID constant-pressure control and supports analog signal input, which can replace the old control structure, reduce wiring and enhance the stability of the control system.

In terms of the monitoring of electricity consumption, the EASY LINK function of PLC acquires the electricity consumption and analyzes it. When the consumption exceeds the capacity listed in the electricity contract, the control system will partially unload the water chiller of high electricity consumption to maintain the balance. In addition, the system will also calculate the cooling demand, allowing the PLC to shut down the extra chilled water outlet in time and reduce unnecessary waste.

PLC and HMI are the primary control and operation parts in the control system. Due to the reason that there are many components in the control system on every floor, correct and fast data transmission becomes relatively significant. Network modules are the parts to enhance the convenience and flexibility of data transmission. Delta recently launched network modules for DVP-SV series PLC and DOP-AE series HMI, offering more various data transmission types and supplementing the series communication structure used in the past. By adopting the existing network in the building, the construction staff does not need to consume too much wire on the series communication wiring, and thus the duration of the construction will be greatly reduced.

In addition, such a control system can easily reach synchronous monitoring among many HMIs to many PLCs and gather all the data to SCADA software for data management. This solves the problems of inconvenience caused by the series communication and enhances the real-time data communication. What is more, The PDA wireless transmission provides instantaneous alarm function. That is, when the PLC detects any abnormality, it will actively and instantaneously announce an alarm in case the serious error extends.