We are experiencing an issue with a B&R PLC after an interrupted project transfer and would appreciate any guidance to reset IP address of X20CP0410 controller.
Background
We were transferring a project to a B&R PLC. Project got transferred to PLC but after transfer PLC ( Controller) tries to reboot and this process was taking too long. After waiting for an 2 hrs. We have cancelled transfer. Now we are not able to re-connect PLC. IP address of PLC got wiped out.
For the past two days, we have been trying to reset the PLC and regain access without success. Since we are relatively new to the B&R environment, we may be missing a recovery step.
Boot Mode Attempts
Following instructions provided by a colleague, I attempted to place the PLC into Boot Mode and observed two repeatable scenarios.
Scenario 1
Power off the PLC.
Power it back on.
Hold the Reset button for approximately 30 seconds.
LED Status:
R/E = Green
RDY/F = Off
IF2/ETH = Green
Scenario 2
Press the Reset button for less than 2 seconds and release it.
Press the Reset button again for approximately 5 seconds.
LED Status:
R/E = Red
RDY/F = Yellow/Amber
IF2/ETH = Green
In both scenarios, the PLC is not detected by the B&R engineering software.
Troubleshooting Performed
Network Diagnostics
Installed Npcap.
Used Wireshark to monitor network traffic.
Checked for ARP requests and responses.
No network activity from the PLC was observed.
Direct Ethernet Connection
The PLC was connected directly to a PC using an RJ45 cable.
All other network adapters were disabled, and the dedicated NIC was configured with the following IP addresses during testing:
192.168.0.10
(Specific desired IP before change)
192.168.1.10
192.168.0.2
Subnet Mask:
255.255.255.0
The PLC was not detected in any of these configurations.
USB Connection
I also attempted a USB connection.
However, no new device appeared in Windows Device Manager when connecting the PLC. This makes me wonder whether the USB port is intended only for service/input functions rather than communication and project download.
Questions
Do the LED combinations described above indicate that the PLC is actually entering Boot Mode?
Is there a default Boot Mode IP address that should be used?
Should the PLC be visible through ARP broadcasts or Automation Studio even when no application is loaded?
Are there additional recovery steps that can be performed after an interrupted transfer?
Is it possible that the controller firmware or bootloader has become corrupted?
Are there any specific Ethernet or USB recovery procedures recommended for this situation?
Any troubleshooting suggestions or recovery procedures would be greatly appreciated.
I’ll try to describe in short words the system behavior in BOOT mode:
If a system is in BOOT mode, it’s normal that you can’t establish a online connection.
In BOOT mode, the system does not use any of the projects configuration data, and does not start the complete online protocol driver.
In this mode, the PLC is configured as DHCP client, so it doesn’t have a predefined IP address but is trying to get one from a DHCP server. Additionally, the SNMP driver is activated → so at least you should see the system in “Online → Settings → browse for targets”.
If no DHCP server is present, you should see the PLC with an IP address of 0.0.0.0 (which means “not yet configured by DHCP”).
Just transferring an Automation Runtime is possible in BOOT mode, either via serial connection or via an IP connection that was temporary set by a DHCP server or by manual setting via “Online → Settings → Browse for targets”.
If you can’t find the PLC with “Online → Settings → Browse for targets”, it could have some network related reason. So trying to setup the system via a prepared USB Stick would be the best option to try in my opinion.
For preparing USB stick, please follow the instructions here for scenario 1, case 3:
Switching to boot mode, please see here:
He’re some short answers to your questions:
1)
if R/E is solid red and RDY/F is solid yellow, the system is either in BOOT or in SERV mode
2)
No, the system in BOOT mode is configured as DHCP client
3)
Maybe, I’m not completely sure. I think you won’t see any ARP broadcasts, but at least in an early boot phase you could see the DHCP discover packages sent from the PLC… but as the PLC doesn’t has any IP setup at this point in time, you would just see it but can’t connect.
4)
I would propose trying the USB stick initial installation unsing an empty project just having a suitable IP setup as described above (to rule out any project related issue at this point).
5)
I can’t swear, but I don’t think so as I’m not aware of any possibility to overwrite the Onboard AR by application.
6)
see 4)
You never need to wait 2 hours; it makes no sense. You very likely have changed your IP address, and after rebooting the PLC, it has booted with a new one. This is question of max minute(s). The point is that you can not see it using online browsing, with newer AR and AS, this option is disabled by default for security reasons, so you have to enable it in project configuration. If you are stuck there and you are new with B&R and perfect suggestion and reply from Alex did not help you, I think the easiest way is to get in touch with B&R support. Do not waste other hours. It is easier than it might look like.
Hi Alexander, Thanks you for your reply. Yes, after connecting through DHCP server. I could get connected now. Once it got connected, I have changed settings to static IP through B&R.
Thank you for your suggestion to contact B&R Support. I was actually in the process of preparing a support request when, during my research, I came across this community discussion.
I decided to give the suggested approach a try, and I’m pleased to say that it worked successfully.
I’m very happy if you ask this kind of question here first. Because this is a general question, and suggestions on how to proceed can be obtained quite fast here. Support is an option when you really struggle with your issue for a long time. So it is up to you where you publish your question; we always welcome all types of questions and knowledge sharing here in the B&R Community.