Monitoring System Of Heat-exchanging Station Based On PLC And Configuration Software

The monitoring system of heat-exchanging station based on configuration proposed inthis paper is a remote monitoring system of heat-exchanging station combined heatingventilation engineering, computer technology and communication technology. The systemcan real-timely collect data and monitor the operation of the heat-exchanging station at thescene of the production. Due to the high communication ability and flexible software function,it also can realize the remote management of field equipments based on network.The monitoring system of heat-exchanging station adopts the control scheme of independentmonitoring of each heat-exchanging stations and the centralized management by monitorcenter. Siemens S7-300PLC is selected as the control of lower machine, and WEINVIEW6056i touch screen is employed as the human-computer interaction interface at the scene ofthe production. They constitute the independent on-the-spot monitor system. The system canindependently operate and save the operation parameters without the control of the computerin monitor center. Both manual and automatic control manner can be selected. By functionalmodule of PID algorithm, it can control the temperature of the second return water to achievethe set value. At the same time, the constant of pressure at constant pressure point and thesteady of the pressure difference between supply water and return water are adjusted bycontrolling the circulating pump and the make-up pump. Finally, the real-time online monitorof some main parameters, such as the temperature and the pressure of supply water and returnwater in both the primary network and the secondary network, is achieved.Adopt Delphi to development upper unit configuration software, and researched thecommunication mode between PLC and touch screen, and between PLC and upper unitconfiguration software. The upper unit of monitor center communicates with many PLCs atthe heat exchange station site by industrial Ethernet to achieve the remote networkmonitoring function. Configuration software configure animation interface of technologicalprocess in heat-exchanging station. It has many functions, such as the storage and analysis ofdata, the query of historical data, trouble diagnosing and alarm, and so on. By collection data,the heating company can timely and exactly monitor the operation situation at the scene ofthe production, and adjust the heating parameters to ensure the heating system to operateeconomically, safely and stably.