Networking Issues with 2 SLC 5/03's and 2 1761-NET-ENI's

[SandwichMagic]

Howdy.

So I am trying to create a small network of just 2 SLC 5/03's and my programming laptop. The SLCs are connected via RS232 to some 1761-NET-ENI modules, in order to make them ethernet compatible. I am pretty positive that I correctly configured both of them, assigning them different IP addresses and making sure that the other processors are in the message routing table. In RSLinx my drive is the Ethernet devices driver (not the Ethernet/IP driver) and I was able to see straight through the ENI's to the PLCs. The keyword here is "was". I have successfully been able to download to the PLCs previously in the past, only 2 days ago in fact. But when I got back to my set up yesterday, the first SLC wouldn't show up in RSLinx, it would only appear as a NET-ENI. As a result, I can no longer download to that PLC. I believe I have narrowed it down to the PLC, as switching which ENI each one is using provides the same results. I have also noticed that on the downloadable SLC, I see the RS232 indication LED flash every so often, indicating that there is communication, but on the non-downloadable SLC, the RS232 indication LED is totally blank, not lit at all. I have tried factory resetting the NET-ENI's and the results haven't changed. I really don't know what I could have done to the SLC, I've downloaded to it maybe twice, and hardly ever messed around with any of the internal settings I don't think. I suppose I could reset the SLC to factory defaults, but I don't actually know how to do that, and would be afraid that there would be some other settings that I wouldn't know to change. I guess any kind of direction would be much appreciated.

Disclaimer: I apologize beforehand if I was unclear about something, truth be told I am a pretty amateur automator. I am a TA for a PLC/Electrical Maintenance program at my school (yes, it's true, I am one of those dreaded college students), and while I feel that I am pretty alright at raw programming, this networking stuff is really what I need to work on.

Anyways, Any and all advice is always appreciated!

Thanks,

Conor

 

[Phil Buchanan]

Connect to your SLC over serial and check the comms settings against your working unit. You could have made a comms change and then downloaded it.

It would be worth a look since you have determined the problem is with the processor and not the NET-ENI.

 

[Firejo]

It sounds like the SLC's channel 0 port (the serial port) is no longer a DF1 full duplex port at 19200 baud. Check to see how the port was configured in the last program you downloaded.
You may very well be at a point where you need to default the processor but it’s actually pretty easy.

To reset the SLC5/03 to its default settings:

• Power down the rack and pull the SLC out.

• Disconnect the battery connection.

• Next to the battery you will see a large capacitor (usually green)

• On the bottom side of the board you will see where the two leads from the capacitor come through the board. Using the tip of a screw driver (or something equivalent) short the two capacitor leads together and hold for a couple of seconds (you’re dumping the capacitors charge. Make sure the battery is disconnected before you do this).

• Restore the battery connection and reinstall the processor into the rack.

o Not required but I always like to make sure that the key run switch is in the program position before re-applying power to the rack

• Power up the rack and the processor should now be in default.

o Keep in mind that there will no longer be a program in the processor so you won’t be able to go online with it until you do a download however it should show up in Linx.

When you’ve done this the SLC5/03’s channel 0 port will now be at 19200 Baud, 8 data bits, no stop bits and the error checking should be set to CRC. I believe these are the default setting for the NET-ENI but I’m not 100% sure about that one.
With that, next time you download make sure that the channel 0 port in the program is set to the settings above.

 

[SandwichMagic]

Ya know, now that you guys mention it I do believe that I might have downloaded a program with a different communications configuration, Didn't realize that at the time but I believe I did do that. Thank you for pointing me in the right direction and for the steps on defaulting it.

Thanks a ton!

-Conor