Connecting to PLC over Ethernet

[Jenny 0]

I have a CLICK Koyo PLC part number C0-00DD1-D, that I want to connect to my computer over a local Ethernet network. The PLC has a RS485 port. Does anybody know how I can accomplish this? I was thinking if I can use a serial RS485 Ethernet converter/server. Anybody has experience connecting PLC's remotely over a LAN network?

[Joan M 3]

DISCLAIMER: I’ve never used this brand. I’m always using Ethernet connection PLC’s from Beckhoff. After looking around on the Internet a little bit… I’ve been able to see a small PDF file with the specs of your PLC: http://www.automationdirect.com/static/specs/c000dd1d.pdf The PLC supports only RS232 Modbus RTU through RJ12. There is another model that seems to have RS485 like yours. (in the same PDF file there are the extra specs). If you want to be able to remotely connect to the PLC you will need two things: 1. PLC SIDE a. A bridge that will receive/send Modbus RTU through the Ethernet (as you suggest). b. Cable from the PLC to the bridge. 2. PC SIDE: a. A bridge that will receive/send Modbus RTU through the Ethernet (as you suggest). b. Cable from the PC to the bridge. PLC ==== CABLE ==== BRIDGE ------ ETHERNET CABLE ---- BRIDGE ==== CABLE ==== PC Hope this helps.

[Jenny 0]

Thank you for the information. Just to update this thread: I had this old serial RS232 Ethernet converter: http://www.usconverters.com/index.php?main_page=product_info&cPath=66&products_id=225 laying around, I tried it out but it didn't work, I suppose its because this particular converter does not support Modbus over Ethernet. As far as I have read elsewhere RS232 Modbus over Ethernet is not the same as standard RS232 over Ethernet. I guess I will have to invest in a proper converter although the seem outrageously pricy.

[Joan M 3]

Probably they'll be expensive... if that is the case you could look for a new controller that can natively connect to the LAN. I don't know if that is posible or not... It is always difficult to get those things working... a small mistake in one cable, electrical noises... any small issue and you can't even monitor it and you could lose entire days with that... after time working that way I decided to stop using things without ehternet ports... I'm only using DEVICENET to connect robots to our devices and CANOpen to connect to drives and third party peripherals, but appart of that ETHERNET (EtherCAT) everywhere.