SVX9000 Drives on Devicenet

[B Fix]

All,

I am having a Devicenet problem. I have 4 seperate Devicenet networks. Each Devicenet network has it's own SLC 5/05 associated with it and it's own 1747-SDN. Each network has 6 drives on it and that is the only thing on the network.

I have set up 3 of the networks already and can see the drives fine in RSNetworx and control them fine from my PLC. The last network is the one I am having problems with. I can control the fans from the PLC (start, stop, etc.) but when I go into RSNetworx, it sometimes sees some drives sometimes does not. The last two times I have tried it, it only finds node 1 (a fan) it doesn't even find the devicenet card at node 00. I was able to sometimes see the devicenet card and was able to map my fans in so that is why I am able to control them, but I can't see anything in RSNetworx and I am stumped. I am using a 1771-SDNPT driver for communicating with the network through linx. I called Rockwell and they had me delete the driver, try all of the 4 ports that it gives you, and also tried deleting my harmony files and resetting my computer. None work. All the other networx still work and I can see the cards and the 6 fans, just this one isn't working and when I tried this morning it only found node 1 again. I am very stumped, any help would be greatly appreciated.

 

[Ken Roach]

Since three other systems work fine, I think that a firmware or software problem is unlikely. It sounds like all these systems were purchased and configured at the same time, so the firmware in the SLC-5/05 and 1747-SDN modules should be the same.

Since you are using a 1747-SDNPT driver, there could be a physical problem on the Ethernet or on the DeviceNet.

Do you have any trouble connecting to the affected SLC-5/05 itself over Ethernet ? The embedded web page in the SLC-5/05 gives some good media counters for diagnostics of the Ethernet port, and the RSLinx Driver Statistics can tell you how well communications is runningn to a device when that device is the only one using RSLinx. Make sure you have a Diagnostic File defined for Channel 1 in the SLC-5/05 and monitor that Diagnostic File for errors.

On the DeviceNet, do the usual checks for voltage (24V at the power supply and no less than 19V at the furthest-away node) and for termination (with power off, measure 60 ohms between blue and white wires).

If you are using shielded wire on the DeviceNet, trace the shield and be sure it's grounded (along with the DNet power supply V-) at only one point.

If you can get your hands on a 1770-KFD or 1784-PCD card, you could find out if the network itself is the problem (you would have similar problems browsing) or if the 1747-SDNPT driver and route is the problem.

After these simple tests are done, the next steps usually involve an oscilloscope and/or DeviceNet NetMeter to check the signal levels and quality on the network.

 

[B Fix]

Thanks for the reply.

I don't have any problems connecting to the SLC-5/05 when I connect over ethernet, it is really slow, but that is how it is for the other SLC-5/05 that are working correctly with their Devicenet networks.

I do have a rockwell media checker that I will probably have to go onsite sometime next week and use on the Devicenet, but what I don't understand is, why can I control and see the fans in my PLC but not in Networks? All the lights on the drives and the devicenet card in the rack are solid green and happy. If there was a problem with the wiring wouldn't I not be able to control the drives?