CITECT MODBUS COMMUNICATION

[ASMI123]

Hii...everyone. Im using Citect scada. There are 10 temperature controllers(same brand) with RS485 modbus communication. That 10 temperature controllers are connected in loop with each other(slave devices). And finely they connected to the citect scada pc(master). The temperature controllers PV address is 400001 and SP address is 400002. Now i want to communicate that temperature controllers to the Scada pc. Can I define different IODEVICes in express wizard in scada for every individual temperature controllers or define only one iodevice because only one rs485 cable is connected to the scada pc from temperature controllers. Please explain if anyone know... im new in that. If i defined different iodevices for every individual temperature controllers in scada then it is possible to define iodevice number in every temperature controller . I get confused plz help Edited December 2, 2015 by ASMI123

[PLCRune]

You have to create different IO devices for each controller you want to communicate with. All modbus slaved should have different modbus adress. After you have one controller up and running go to project editor Communication and I/O devices. Take the one who is working and make changes to adress field. The number and Name also have to be unique. Press Add. Do this with all your controllers.

[ASMI123]

THANK YOU FOR REPLY. Im using 10 temperature on/off controller. which are of the same brand. The PV address is same 40001. and SP address also the same i.e 40002 for all temperature controllers. I think you are telling that i have to define different Iodevices for different slave devices i.e temp. controller. e.g Iodevice1 - 1st temperature controller, also defining there PV address 40001(which are same for all temp controllers) Iodevice2 - 2nd temperature controller, also defining there PV address 40001. Iodevice3 - 3rd temperature controller, also defining there PV address 40001. . . . Similary upto the "Iodevice10- 10th temperature controller,also defining there PV address 40001" This is all i need to configure in express wizard of SCADA& after that in IODEVICE configuration. AM I RIGHT.. IS THIS YOU WANT TO TELL ME.

[ASMI123]

I done this....Similarly i have to define for other 9 temp controller. AM i right???

[ASMI123]

I think that address field specifies the station number of the slave device. I have to only change the Iodevice and address field for every temperature controller.

[PLCRune]

This is correct But also the number field have to be unique on all your IO devices.

[Sai Krishna]

you create different IOdev & adresses can be same .First it identifies IODev and then check its adresses value; but tag name should  be unique.