1788-ENBT Losing IP Address

Hi,

I have been hunting around for some information but can't seem to find anything directly associated with the problem I am having.

I have 10 Flex Logix PLC's all connected to the same ethernet network, (10.8.64.xxx).

We have recently been experiencing a lot of power outs at the factory. If the power is off for a short period of time, everything starts back up OK.

However if the power is off for longer than about 10 minutes, all of my Flex Logix PLC's lose their respective IP addresses.

I then have to go into the BootP server and reset them all, at the same time as disabling the BootP.

I have looked in the module configuration using RSLinx, and the IP addresses are all set to static and it appears the BootP is working as it should, but when the power goes off I lose the IP addresses.

There's no problems with the battery's because I'm not losing the program that is on the PLC's.

I dont have an issue with any of the Control Logix PLC's on site, only the Flex Logix.

Any help or hints as to what is happening would be much appreciated.

Cheers

Mark

Mark,

What firmware revisions are the FlexLogix CPUs and the Ethernet/IP daughtercards running?
I believe there were connectivity related issues with slightly older major revisions.
Since the FlexLogix series is discontinued, the latest CPU/communications modules firmware should mitigate the issues you are experiencing.
For the 1794-L34 Series A or B the last release was 16.022; for the L33s, 13.033; the 1788-ENBT latest released firmware was 3.001.
I'd try updating all components to the latest available firmware.
http://compatibility.rockwellautoma...roductDownload.aspx?keyword=PC Card&crumb=112

Hi Dmargineau,

Thanks for the reply.

My ethernet card is running version 2.003, and my 1794-L34 is series A and is running version 15.006.

I have checked the link you sent and there are no known issues, but it wont do any harm upgrading to the latest versions on all the equipment.

The thing that is funny, is that we had powercuts before and this never happened, it has only started recently.

Cheers

Mark

OK just to add a little bit more.

I have been speaking to a colleague at a different plant and he is having exactly the same problems with some PLC's on his site.

The only common thing we can come up is that the networks are on managed Hirchsmann switches.

I am currently reading through the manual for the switch to see if I can come up with anything.

If anyone has comments why the switches could be making the PLC's default back to BootP it would be appreciated.

Thanks

Mark

Hi guys,

sorry to jump on your old post, i am having the exact same issue,

my flexlogix plc 1794-L34 series b, the 1788-ENBT is connected also.

the machine has been running for 15 or more years and we are suddenly getting the issue if we power down the enbt loses the ip settings.

Plc is running version 13.

@Marknightingale did you ever solve your issue?

thank you