Abstract : This paper, based on the MCGS (Monitor and Control Generate System) configuration software, takes the water supply pump station monitoring subsystem of a water plant as an example. Through the design and development of the system, it illustrates a typical application of MCGS in the water supply industry. This paper focuses on the configuration method of various modules of the Advantech ADAM5000 system and the read/write operations of the module devices using serial synchronous communication within the MCGS configuration and operating environment, as well as the programming process of the water supply pump station module control software.
Keywords : MCGS; real-time database; parent device; child device
The application of ADAM5000 at the auto inspect and control system in water factory
Luo Jianguang
(XinJiang Productivety Center, Urumchi 830008)
Abstract: This paper expatiates a type application about MCGS in water supply. And the paper is based on the configuration software MCGS by designing the inspect and control system of water pump in a water factory. The important of this paper are to read and write ADAM5000 by serial port and compile the program for controlling the water pumps.
Keywords: MVGS; real time data-base; father-device; sub-device
0 Introduction
A water plant in a certain regiment in Xinjiang has a water supply capacity of 100,000 tons/day. For many years, it has been unable to dynamically monitor the process flow and understand in real time whether the production equipment is operating safely. This has brought great inconvenience to management and also poses certain risks.
In 2009, the regiment decided to use MCGS from Beijing Kunlun Tongtai Automation Software Technology Co., Ltd. as the development platform to establish the "Water Plant Automatic Monitoring and Management System," which solved many of the above problems.
This article takes the water pumping station control subsystem as an example, focusing on the configuration method of each module device of the ADAM5000 series and the read and write operations of each module device control through serial communication via the user window in the MCGS configuration environment, and completing the software programming process of ADAM5000 control of the water pumping station.
1. Composition of the water plant monitoring system
According to the water treatment process requirements, the automatic monitoring system of this water plant consists of six parts: the intake pump house system, the chemical dosing and coagulation subsystem, the chlorination and disinfection subsystem, the filter control subsystem, the delivery pump house system, and the power distribution control subsystem. Each control subsystem uses an ADAM5000 to perform on-site monitoring and data processing. MCGS communicates synchronously with the ADAM5000 of each subsystem via serial port (RS232/RS485) to collect data, or outputs data from the real-time database to external devices to achieve control and operation of external devices. The water plant's automated monitoring system is shown in Figure 1.
2. Configuration and Operation of MCGS
2.1 Configuration and Operating Environment of MCGS
MCGS is a development tool that can run on various 32-bit Windows platforms from Microsoft. The architecture of MCGS consists of five parts: the main control window, the device window, the user window, the real-time database, and the operation strategy (see Figure 2). During operation, MCGS collects and processes real-time data from the field and facilitates on-site operations for operators through animation display, process control, alarm handling, and report output.
2.2 ADAM5000 Equipment Configuration Method
The device window is the background operating environment through which MCGS establishes communication with external devices that are the objects of measurement and control. MCGS divides the actual external devices into independent devices (devices that can work independently and complete specific data input and output functions), parent devices (devices that do not directly process data input and output but play a role in managing the work of other devices), and child devices (devices that have the function of processing data input and output, but only together with the corresponding parent device do they form a complete working system).
In the MCGS device window, first select the intelligent module component from the device component box and configure it in the window. Then, according to the type and characteristics of each module device in the ADAM5000 series, select the serial port synchronous communication mode. That is, a communication processing mechanism in which multiple communication sub-devices are connected under the serial communication parent device. By establishing a transmission channel connection with the external actual ADAM5000 device in the form of a parent device, and then setting the relevant attributes of each ADAM5000 module, the real-time data synchronously collected by each external ADAM5000 module is sent to the real-time database through the device component, or the data in the real-time database is output to each external ADAM5000 module device. According to the relevant information, it is sent to other parts of the system in the form of events for control calculation and process scheduling, so as to realize the real-time monitoring and control of the working status of each external ADAM5000 module device by the MCGS system.
The application control program for the water pumping station is developed in the control strategy of the MCGS software platform. Variables are stored in the real-time database to complete the equipment configuration, which enables real-time monitoring and control of the operating status of the pumps in the water pumping station.
2.3 MCGS 's read/write operation process for controlling various modules of ADAM5000
At runtime, MCGS uses Active DLL components to build device drivers, which are then attached to MCGS via a standardized OLE interface, forming a unified whole. The device driver and MCGS run within the same process to support data exchange between programs and also to enable interoperability between different software. To operate the various ADAM5000 module devices in MCGS, you must first ensure that the corresponding ADAM5000 device has been selected in the device toolbox. Then, in the device component management tool, register and select the ADAM5000 module devices you wish to use.
MCGS first checks whether the ADAM5000 module device meets the interface requirements, and then calls the interface function (GetDevName) of the module device. Then, it calls the interface function (InitINewDev) in sequence, initializes the properties of each ADAM5000 module device, reads the property function (DevType) to determine the type of the module (0 is the parent device); then it reads the property function (DevStyle) to determine the category of each ADAM5000 module device as a sub-device (the sub-device should be set to the category of the parent device component), and returns the type name of the module device. This type name is finally displayed in the device toolbox to identify the corresponding device component.
Open the device properties window and set the properties of the ADAM5000 module, that is, define the channels of the ADAM5000 module, which establishes the connection relationship between the channels of the device component and the internal structure of the ADAM5000. When the operator draws and presses the corresponding button in the user window, MCGS calls the interface function (SetDevPage) to drive the ADAM5000 device (the source code of the application control program has been written into the control strategy); MCGS reads the channel information of the device by calling the interface function (GetChlType) and displays the channel connection status. Based on the transmitted data, the MCGS system realizes real-time control of the external ADAM5000 module. The user window of the water pumping station is shown in Figure 3.
3 Design and Implementation of ADAM5000 Control Software
3.1 Process Flow of Water Pumping Station
The water pumping station is part of the "Water Plant Automated Monitoring and Management System." Its main equipment consists of five centrifugal 5605-44/1870/49 type water pumps, of which pumps # 1 to # 5 are constant-speed pumps, equipped with Y450-36/4/440 type pumps.
Motors. Each water pump is equipped with one outlet electric valve and one water-lifting solenoid valve; two vertical submersible pumps (for drainage); and two vacuum pumps (for vacuum lifting of water from the water pumps). In addition, the equipment includes 12 high-voltage switch cabinets, 16 low-voltage distribution cabinets, two 800kVA transformers (one main and one backup), two ultrasonic flow meters, one pH meter, one residual chlorine analyzer, six capacitive water level gauges, and two pressure gauges, etc.
Centrifugal water pumps are self-priming when the effective water depth in the clear water tank is above 1.8m; below 1.8m, vacuum water lifting is required. The number of pumps to be started and stopped is determined based on the water level, service pressure, and flow rate requirements of the clear water tank. The pump operating status is then promptly reported back to MCGS, and real-time measurement data is provided to the water plant dispatch center. The start and stop of the drainage pumps and vacuum pumps are determined by the workshop operators based on the water level in the collection well and the requirements for vacuum water lifting.
3.2 Control process of water pumping station
The pumps in the water supply pumping station are controlled by both manual and automatic methods. When the pump start command is issued, the system determines whether to start the pump based on the operating status of the water intake pumping station, the water level in the clear water tank, and the pressure of the water leaving the plant. If the above conditions are met, the motor is started and the corresponding outlet valve is opened.
If the water pump fails to operate according to the program, an alarm will sound. If the water pump motor malfunctions, the corresponding valve will automatically close and a fault signal will be issued, while the standby pump will automatically start operating. If a pump shutdown command is received, the corresponding outlet valve will be closed first, and then the water pump will stop operating. Based on operational experience, each time a water pump is added, the standard is to put into operation a pump with the operating flow rate that meets the factory pressure; when reducing the number of operating pumps, the standard is to remove pumps with a large operating flow rate that exceeds the factory pressure by a significant margin. The control flow of the PLC for the water pump house system is shown in Figure 3.
4. Conclusion
The system employs a combination of MCGS and ADAM modules to monitor the water plant's processes and equipment in real time, significantly improving management efficiency and saving costs. After more than a year of operation, the water supply pump station monitoring system, as a subsystem, has basically achieved real-time monitoring and control of the pumps and equipment in the water supply pump station. The entire system also provides real-time monitoring of the process flow of the intake pump station, chemical dosing room, sedimentation tank, filter, and backwashing pump station, as well as the operation of the sludge discharge trolley and the formation and disruption of the sludge discharge siphon. To date, the system has been operating reliably and stably.
References
[1] Training Material Compilation Group. MCGS Software Programming Manual [M]. Beijing Kunlun Tongtai Automation Software Technology Co., Ltd., 2010
[2] Jiang Jizhong et al. Automatic Control Systems for Water Supply Industry [M]. Nanjing Hohai University Press, 1999.
[3] Zhang Xiaoming. Practice of MCGS in the automated monitoring system of Dongzhuang Water Plant [J]. Electrical Drive and Control, 2004(4)
About the author:
Luo Jianguang, male (Han), from Urumqi, is the director of the project department at the Productivity Promotion Center.
Contact information:
Postal code: 830049
Address: School of Electrical Engineering, South Campus, Xinjiang University, No. 1230 Yan'an Road, Urumqi, Xinjiang
Telephone: 15999126303
Email: [email protected]
