During testing of hydraulic support, the test operator needs to handle large amounts of test data. If you rely solely on the kinds of manually processing test data, not only cumbersome and time-consuming, and error prone. Therefore, it is necessary to establish information management systems to a variety of experimental data for unified management.
Based on test data flow, conducted by PowerDesigner data model design. Power Designer is Sybase's CASE (Computer Aided Software Engineering) tools, you can easily to the information management system for analysis and design. And DataArchitect module is the core of PowerDesigner tool, you can easily use DataArchitect Kotoshige conceptual data model (CDM) and physical data model (PDM) design.
Figure 5 .PLC wiring diagram
Establishment of a database using Access and through ADO technology to achieve a connection to the database. ADO object model defines a set of programmable objects layered. This object model includes three basic core objects: Connection, Command, and Recordset. Use VB6.0 complete interface design, so as to establish the test process management information system to facilitate the management and reporting test data printing process.
Currently, the communication between PC and PLC are mainly two: one is PC always in the driving position, sending and receiving data by the PC regular issue commands, and PLC in a passive position; the other is PLC always has priority [4]. Taking into account the monitoring system monitoring and control functions in the host computer, thus using the first communication.
VB provides serial port control MSCoinm, which controls the communication process encapsulates the underlying operating, users simply set up, monitor MSComm control properties and events can be user-defined communications protocol, no additional investment, and has a peripheral device to communicate with convenience and easy computer control software development and other characteristics, especially suitable for small-scale computer control system.
PLC using free communication interface protocol, the host computer by setting properties and events MSComm control, enables communication, the communication process monitoring system is shown in Figure 6.
STEP7 programming software is Windows-based application software, powerful, mainly for the development program, can also be used for timely monitoring of the user program execution state [5]. This article was developed by STEP7 PLC control program.
PLC control program is pided into two types: automatic control program and manual control procedures. In automatic mode, the monitoring system will test parameters are sent to the PLC, the PLC by car test in a logical order to the output of the switching signal, the control relay on-off switch to control the solenoid valve to achieve in accordance with the initial support, booster , recycling packing and unloading of the loading process executed sequentially until meet the test requirements. In manual mode, the operator can load operation done by clicking buttons on the screen. PLC control procedure work flow is shown in Figure 7.
Figure 6 . Traffic flow monitoring system
Figure 7 . PLC control program work flow
4 Summary
Based on the structure and function of hydraulic support test platform, combined with the coal industry standard "MT312-2000" technical requirements, scientific and rational design of the experimental procedure, described in detail the specific design overall design test rig monitoring system, as well as hardware and software and implementation, setting up an experimental platform hydraulic support performance testing.
REFERENCES
[1]Dong Zhifeng，Wang Shoufeng, Chang Hong，Wu Jian. Mecha¬nisms and Kinematics of Hydraulic Support for Top一 Coal Caving [J]. Journal of China University of Mining Technology，2001, 11 (2): 155-158. (In Chi¬nese) 液压支架试验台计算机测控系统英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_22719.html