Application example of MITSUBISHI CC-Link bus

In the development of hydraulic turbine governor, the MITSUBISHI CC-Link bus is used as the alternate channel between the two PLC:

1. the hardware part of the governor:

The governor of the hardware configuration is mainly composed of two sets of identicalconfiguration PLC: the main board, the power supply module, CPU module, I/O input module, I/O output module, A/D module, D/A module, high-speed counter module, CC-Link communication module. Monitor screen adopts flat LCD computer (with touch screen), and communicate with CC-Link bus, and install PCI CC-link interface card A80BDE-J61BT13.

2.Implementation of data communication between pairs of PLC:

Any PLC system can be defined as a master station or a standby station, and the communication rate between PLC is 0Mbps. The station number is only set on the CC-Link module, and the 0 station is the master station. The communication method is as follows: the X point corresponding to the master station is the Y of the local station, for example, the output of the Y1000 point of the local station is the input of the main station's X2000. Corresponding to the same D register.

3. , PLC, CC-Link software settings using Mitsubishi Co GX Developer software settings:

CC-Link module number: represents the number of CC-Link modules on the PLC substrate, and the governor adjuster has only one piece.

Starting I/O number: indicates the location of the CC-Link module mounted on the substrate. The regulator module is mounted on the eighth slot except the power module and the CPU module.

Type: does the CC-Link module define the system as a master station or a local station?. (relating to the station number switch settings on the module).

Total number of links: only in the main station need to set, due to the existence of B sets PLC (local station) and PCI CC-link card, so it is the 2 set of local stations.

Remote input (Rx) refreshes the soft components: set to m2000. Remote input (Ry) refreshes the soft components: set to m4000.

Remote input (RWr) refreshes the soft components: set to D1000. Remote input (RWw) refreshes the soft components: set to D2000.

Send number: when a communications failure, the retry again link. Station information specifies: when clicking on the station information, the following picture appears

4. CC-Link data communication between PLC:

The above communication failure judgment event is only 200ms. When the communication fails, the data will not be cleared, and the data before communication failure will be maintained. The local station due to the occupation of the 4 stations, each station to read and write data for the 4 and 32 I/O, the amount of data communication is 128 (32bit * 4) a variable and 16 (4Word * 4) a word variable, because it is not great exchange of real-time data in the control system volume. The exchange of data are: gateopening, unit residual voltage frequency, gear measuring frequency, unit power, real-time head, all the given value (a given frequency, opening, given the given power, opening limit and so on). As for the need for more data interchange capacity, flag bits are used. Such as: a variable bit1=0 when sending packets of DATA1_0[16] variable bit1=1 when sending data packets of DATA1_1[16].. Variable bitn=0 packets DATAn_0[16] variable bitn=1 when sending data packets due to DATAn_1[16] communication bit variable is n=128, the communication data (send and receive) DATA = 2 x 2 x 128 x 16 = 8192 WORD. The communication data can meet the requirements of the governor system.

5. The data communication between CC-Link and IPC: IPC is PPC123 type LCD computer Advantech, install PCI CC-Link A80BDE-J61BT13 and CC-Link bus communication interface card. The interface card is preset to support various OS drivers, Windows2000, Windows, NT, Ver 4, and so on. You can set the relevant parameters on the attached CC-Link Utility software. The interface card is used as the local station, and the parameters such as station and communication are the same as the slave station settings of the PLC CC-Link software. Through the dynamic library interface function attached to the CC-link interface card, you can use VC and VB to develop applications to achieve data communication with other stations on the CC-link.

6, because the CC-Link mode has the communication speed of 10Mbps, the data exchange of the two computers is synchronous basically, and it provides real-time data for the regulation of the hydraulic turbine. And this method is an open bus, with high reliability. The most valuable is that this method has a high cost performance, the right price, appropriate communication data, high communication rate, reliability and so on.