adding a plc to a dh 485 existing network??

[LoggerHead]

I am adding a plc 5/03 to an existing network that has 4 other plc's communication through a DH-485 communication interface. My plc's are adressed nodes 1-3, I have added a plc and it is now my first plc from the DH-485. Its the first one in the daisy chain. I thought when I added one it would see it and show it on a new node. This didn't happen. It doesn't show it at all and starts to knock out my comms between my other plc's and my computer. Do I have to change the plc that was on node one to a new node number? Do I need to do this in the processor? I have worked with AB plc's alot in my prior job but they were all stand alone processors. I have very little experance with communications.Any direction would be a big help. Thanks in advance
Daymond

 

[SteveMeisel]

Why not just make the new processor node #4. Otherwise you will have to change node 1 to 2, 2 to 3, 3 to 4, to make room for the new #1. The network does not care which order they are wired in, just as long as there is no duplicate nodes.
You will have to do this offline then upload the changes to the processor. Just make sure that you are sending it to the correct processor if doing it over the network. A good safegard is to unplug the processor from the network then upload to it.
We once had a contractor in over the weekend and they made some changes to a plc offline, uploaded, then left. Well there are 10 other plc's on the DH+ network. They sent the program to the wrong processor and we did not find it until Monday morning after loosing several hours of production.

 

[xyzz]

The physical location of a node on the DH485 has nothing with it's node number.
You have to assign new unique node number and name to the new PLC and reflect them in the processor properties.
Also, define the PIC communication driver in the PLC channel configuration.
The correct maximum node number must be set in all nodes on the network.

 

[LoggerHead]

I got it working. Its wasn't that hard once I quit trying to use the network to set up th processor and used the laptop to get the node right. thank for all the help.
Daymond