Can't connect to X20CP3584

First of all ,Your support is highly appreciated for this issue and I would like to thank everyone who contributed a response, as I have learned a lot from you and your contribution.
While trying to connect to cpu 3584, there is no connection establish .how can i define ip address for Pc and Plc
The message appeared waiting plc and didnot enter on the program

Hi Mohamed,

If the PLC is expecting a DHCP server to set its IP address, you’ll need to connect the PLC to a network with a DHCP server. Otherwise, the IP can be statically set in Automation Studio. There is a helpful post from a while back which can help you connect to the PLC if you don’t know its IP address: How to Connect to a PLC with an Unknown IP Address - Share Info & Ideas - B&R Community (

I’d also recommend double checking the status LEDs on the PLC. When the application is running, the R/E light at the top will be solid green. If there is some error, you may have trouble connecting regardless of the set IP address. Your picture shows the top three lights as off, but that may just be the moment you took the picture.

If you wanted to find the PLC’s IP address without setting a new one with Automation Studio, you could also use Wireshark instead. See this post: Determining a PLC’s IP Address using Wireshark - Share Info & Ideas - B&R Community (

Thanks sir for your support
By using address ip scanner the following address has been appeared as show in the picture
The question is what ip and subnetmask that be entered from pc network connection properties

I’m not familiar with your “IP Scanner” program but it sounds like you’ve figured out that the PLC is successfully communicating using IP In order to connect to it, your PC will need to be on the same network with a different, unique IP address. The settings you need will depend on the network. However, assuming that your PC and PLC are directly connected with no other devices, any other IP address will work. So you could set your PC to be for example. As far as the subnet mask, the safest thing to try is as this will ensure the connection is only made with IP addresses where the first three octets match.

To learn more about how networks and IP addresses work, you can read this helpful post: A tiny network basics glossary - Share Info & Ideas - B&R Community (

Thank you very much sir for your help.
Is there any description for the diagnostic leds of Cpu ? As example R/e mean run-error …etc

LEDs CPU description you can find here

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Thanks sir,
Your contribution is always effective and useful.

Hi @mohammed_saad465 , no problem. Please mark reply that helped you as a solution. Thanks.

Thanks sir for your effort
The communication has been established successfully after entering the mention IP and submet mask.

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Awesome, I’m glad you got it working!

Congatec is probably not your X20 CPU, MAC-Address of the CPU is lasered onto the left side of the housing and will start with “00-60-65-” (Vendor-ID of B&R)