Remote node interrogation on Ethernet networks

[Blaksun 0]

Hi everybody, I just need some help regarding remote node network participation? I've setup communications between CS1G-H CPU using CS1W-ETN21 and CJ1M-CPU12ETN. My ladder program consists of basic instructions namely SEND and RECV. Also I'm using ports 1 - 4 and will eventually be using ports 0 and 5 - 7 for another CJ1M-CPU12ETN What is the best way to check whether or not the remote node is actually on the network? Via the PING FINS command? Basically, i just wanna know when the remote unit which is in this case the CJ, is actually physically connected? Any help is much appreciated Kind Regards

[edpuente 0]

If I recall well, connect to the network your laptop, with the explorer type http\\ (the plc node address and \0 ex. 198.173.92.10\0) and you will be able to see and modify some basic configuration of the ethernet module of that particular PLC.

[Blaksun 0]

Nope, I need to do the check at the CS1G-H CPU side, not via laptop.. but thx for replying.. nobody else seems to have an idea..

[Fredrix 3]

You could maybe use a lifecycle? A counter incrementing in both PLCs, when it stops, communication is gone... Or is this not what you want to acheive?

[Blaksun 0]

How would this be achieved.. and how would 1 monitor for the stoppage?

[Fredrix 3]

You can use a word which increments in PLC1, send it to PLC2 increment by 1, send back to PLC1 and repeat Steps: PLC1 : Increment, Send to PLC2 -> PLC2 : Increment, Send to PLC1 -> repeat In both PLC you create a timeout function for that word, if the word don't change for a specified time - there is an error Timeout function can be used by making a temp value (old value), Check if current value is different from old value, if not then start a timer (or just increment a word and do a compare on that word), if the value is different then move the new value into the old value Edited 25 Jul 2008 by Fredrix

[PMCR 66]

When you use the FINS Send and Receive commands, you can check the completion codes for the logical port that you are using to see if the FINS command was successful. This is a surefire way to know if the remote nodes are responding. Incrementing a word of data in a remote PLC and reading that value into the main PLC, and looking for the data to change periodically is also another good way to make certain that the remote PLC is online and running. I have used this method many times over the years of different network types (Ethernet, serial, DeviceNet, etc.)

[Blaksun 0]

Hey thx for all the help. I've set up a heart beat on the remote plcs and it seems to work 100%! Much appreciation to both of you! :)

[jylilaht 0]

Where do I find password for that page? I suppose I have some kind of default passwords in there, since there should not be any passwords set.

[edpuente 0]

The password is ETHERNET