DeviceNet scanner error code 77

I have a customer with Devicenet, currently having an error code E#77 show up on the scanner. The scanner in question is a 1756-DND. There are 20 nodes, they are 1734-ADNs. I am having problems with node 20, which has 14 modules connected to it. It was working fine before until i started screwing around with another node that was having problem using RSNetworx and I somehow effected this one.

Connected to the node are 14 IO modules. Starting from left to right I have a IB8, and OE4C, OW4, OW4, OW4, 1734-EP24DC, OW4, OW4, OW4, OW4, OW4, OW4, OW4, OW4 and IE4C.

The network status lights on all the modules are solid green, the module status lights on all the modules are also solid green. The OE4C and IE4C LEDs 3 and 4 blink red. Though I think that may be normal.

From what ive read, there is a size mismatch and most likely the module is configured improperly. I don't understand what this means, I wasn't the one who setup the system to begin with. To top it off, the person who configured it is on vacation.


I barely have any background with devicenet. Does anyone know a solution to this problem?

Thanks!

You can't get much more complex than a network composed entirely of 1734-ADN adapters. The size and configuration can vary for each one, and each one has its own *.DNT configuration file.

So you've bitten off quite a bit to chew on.

Offline, open up the *.DNT file that includes the 1756-DNB, and double-click on that device to examine its Scanlist.

Are there any other 1734-ADN adapters with the same mix of modules ?

Examine the size of the I/O connections for the various adapters that are in the Scanlist.

What's the I/O connection size for the one that is being indicated as correlating to Error 77 ?

Is the Error 77 the only error code being scrolled by the 1756-DNB ?

It's possible to determine I/O connection sizes by sending DeviceNet Explicit Messages from RSNetworx to the adapter, but that's a medium-difficulty process. RA Tech Support can walk you through it, or you can search this Forum for some of those keywords (here's one of mine... sheesh, twelve years ago: http://www.plctalk.net/qanda/showthread.php?t=910)

All the nodes are 1734-ADNs.

At the moment i don't have access to the networx software.

I have some DNT files for each individual node provided by the original company that programmed it, for example node 1. I open the file and it shows me in graph view the node itself and the IO modules. When I go online to find that some of the modules on the node have a different revision than the ones on the .DNT


I also have a .DNT file for the whole network. The graph view shows the scanner, and the 20 nodes. No revision conflicts when I go online.

RSNetworx for DeviceNet is the software that opens those *.DNT files.

You need to open up the one that contains the 1756-DNB Scanlist, and figure out the Input and Output data sizes for the device giving the E#77 error.

Then you need to reconfigure that device with the *.DNT file that contains its configuration.

So start with that first *.DNT file. ZIP and post it, or post screenshots, or describe what you see in detail.

Also, let's be absolutely certain which device is giving you an error.

While the scrolling codes are handy, it's even easier to see the error codes in RSLogix 5000. For a 1756-DNB in Slot 10, for example, the tag "Local:10:S.DeviceStatus[x]" would be a 64 INT array with the status code for each possible DeviceNet slave node in the array.

Switch the Radix to Decimal (it's hex by default) and you'll see Error 77 prominently in that list.

Thank you for helping me with this frustrating error code.

Ill try the above. Unfortunately I can't post any screenshots or files out of confidentiality.

Ill update thread for new developments.

The problem has been resolved. Using RS-Logix 5000, I found the DevNet .dnt file path in the project, opened that in Networx and downloaded it to the scanner a problem went away.