This paper mainly touch screen introduces touch screen the Pro-face touch screen and Siemens-300 series PLC connected to the Profibus network through the bridge Application project Application using Application 6 12.1 inch color touch screen. Realize the centralized Pro-face control Pro-face of Pro-face the whole system, and at the same time can be in the field operation.
First, the foreword
Pro-face is the world's first manufacturer of touch screen manufacturers, in the field of human computer interface has been a leader in the role, the product continues to upgrade, innovation. Now 2000 series, the performance is good, the function is powerful, the interface is flexible, has the very high price to price.
Two, system introduction
System hardware structure
1, PLC selection is S7-300 CPU315-DP series CPU SIEMENS, plus Ethernet module and I/O module.
2, touch screen selection of Pro-face2000 series, the model is: GP2600-TC41-24V.
3, bridge PB-B-MODBUS
4, temperature control table, frequency converter, and other electrical accessories.
System process introduction
PLC is the selection of SIEMENS CPU315-DP as Profibus master, Profibus as a bridge from the station, the site is set to 2. Bridge to Modbus station, so the touch screen as the Modbus from the station.
Have a touch screen GP2600-TC41-24V can plug Profibus DP card, directly attached to the Profibus DP field bus, but this system with the touch screen is more, because of the cost, choose a bridge, the Profibus bus to Modbus bus, to use the RS485 way on the touch screen, 6 touch screen as a slave station.
GP side select Slave Modbus protocol, the site was set to 1, 2, 3, 4, 5, 6 station. The baud rate is set to 9600 or 19200 can be, but both sides need to maintain a consistent set. And when the touch screen side with the Slave Modbus protocol can only use the 4 beginning of the data area, so you need to use a bit operation when only the use of a bit of the beginning of the 4 to achieve a bit.
In order to ensure the reliability of the bus communication, it is required to operate on the GP, but also in the host computer monitoring. GP is placed in the operation of the scene, the host computer in the monitoring room, the same picture effect. Engineering, there is a problem: when the host computer does not operate, GP can be normal operation; PC operation GP side when the crash status. The analysis shows that: in the Modbus network, only the master station can send commands to the station, from the station to respond to the request of the master station, and the request from the station can not take the initiative to the master station. Experiments in Slave do GP, so the host computer operation when the GP can respond to, and GP can not operate. Verified: have a status and control words over the bridge, when the control word is set to different values, you can read and write duplex operation.
This configuration is a more economical way, and the system is very stable and reliable, in other industries more large production line can also be used in this way, it is worth promoting.