Author: IKON Drives Technical Support Department
The main equipment of the air compressor station is an air compressor, an air dryer, a matching filter, an air storage tank, connecting pipes and valves to form an air supply system. Large air compressor stations usually have multiple sets of equipment to ensure the needs of different loads. Ensuring qualified air supply quality, satisfying stable air source pressure, and automatic adjustment of air supply flow are the basic tasks of air compressor station automation. With the continuous improvement of the automation level, the requirement of building an unattended air compressor station has become a development trend, so the monitoring system must meet the following requirements :
l Safety and reliability : Various fault detection and protection measures ensure that the system can operate safely and reliably for a long time
l Scalability: According to the different needs of users, the software and hardware systems can be reasonably designed, so that the system has good scalability and flexibility.
l Ease of use : Good man-machine interface display, multi-language support, simple and convenient operation, the operator does not need high professional knowledge, and can be proficient in operation after a little training.
Figure 1. Field Device Diagram
1. Selection and configuration
1. C7 touch screen:
l 7-inch TFT screen, 800×480 resolution, A8 CPU, 4G Flash, 512M RAM. support:
l Intelligent management, support cloud /mobile terminal access control, strong operability;
l Integrated IKON Drives Cloud cloud service, built-in IKON Drives cloud engine; can remotely realize mobile phone APP, computer cloud website and remote upload and download HMI and PLC programs
2. PLC: T48S2T-e+S04XA+S01RS+S01RS
l T series standard PLC, can be expanded to 7 modules, with one RS232 and one RS485 port;
l The program is permanently saved, the program capacity is 48K, and the instructions are rich, which fully meets the needs of on-site logic control;
l The analog quantity does not need to write any conversion program. On-site temperature and pressure collection WYSIWYG.
l A 485 port can carry a lower computer with different baud rates and data formats at the same time
Figure 2 Schematic diagram of networking
2. Introduction of control scheme
The air compressor station is generally composed of a compressed air station, which consists of an air compressor , an air storage tank (divided into primary and secondary air storage tanks), air treatment and purification equipment and a refrigerating machine. In terms of control, it can be divided into data Acquisition ( exhaust pressure, pipeline pressure and host temperature, etc. ) , inverter control ( controlled by the PLC internal PID according to the set pressure and actual pressure difference , to achieve automatic adjustment), operation settings ( including timing settings, operation parameter settings and auxiliary machine settings ) .
In addition to the above controls, there are also essential human-computer interaction interfaces, and the following control requirements must be realized:
parameter monitoring: The HMI interface displays the pressure value, temperature and inverter operating parameters in real time, as well as the manual automatic switching and modification of the control system, and displays the process diagram;
l Remote control: It can realize computer, mobile phone and web page access, and remotely modify parameters;
l Alarm information can be received and queried historical fault parameters on the computer and designated mobile phone;
l Record and save the data of the pressure during the control operation, and make a graph.
3. On- site control photos
Figure 3 The computer web page runs the HMI project interface and the local HMI terminal
Figure 4 IKON Drives Cloud APP accesses the control screen of 2# air compressor
Figure 5 IKON Drives Cloud APP access operation monitoring screen
4. Part of the program
Part of the HMI program
Figure 6 Air compressor control screen
Figure 7 Parameter setting screen
Figure 8 Trend curve screen
Figure 9 Alarm screen
V. Summary of the plan
1. HMI supports IKON Drives cloud platform, intelligent management, supports cloud/mobile terminal access control, and has strong operability;
2. Integrate IKON Drives Cloud cloud service and built-in IKON Drives cloud engine; make access safe and reliable, and make remote safe and secure;
3. IKON Drives PLC 485 communication supports simultaneous communication of different baud rates, different protocols, and different data formats, and the communication program does not need to deal with timing, which greatly saves the programming time of engineers;
4. The Ethernet PLC is selected on site . The Ethernet PLC supports simultaneous access by multiple upper computers. At the same time, the Ethernet port can also be used as the master station to access other devices, which can be master and slave, which is convenient for debugging;
5. Through the IKON Drives touch screen, you can also remotely upload and download HMI programs, upgrade firmware, and export historical data records;
6. Through the IKON Drives touch screen, you can also remotely upload and download PLC programs, upgrade firmware, monitor and diagnose PLC information.