Modbus TCP questions

Hello everyone!

I'm currently trying to connect a Quickpanel+ to 3 different GE relays. The problem are the drivers and how to communicate over TCP/IP. I thought about using native PLC drivers for modbus TCP/IP (displayed on proficy machine edition as Modicon TCP/IP) and read addresses like it's usually done with PLC. However, I'm trying to emulate this with modsim and nothing happens.

Any ideas on how to work this out? I thought about using GE's Global data, but modbus TCP has already been set-up for this project.

Thanks!

You are on the right track with the Native Drivers. Setup a Modicon TCP/IP driver and add a Device for each Relay.
Once all the IP addresses match and the network is setup properly you will be able to access the Addresses defined in the Relay documentation.
For someone to assist in your troubleshooting you must supply DETAILED information of what you have and how you have everything configured.

Thanks for the quick reply RussB!

Well, I have a QP+ that will read around 15 modbus tcp addresses from each of the three C60 relays. The network addresses are already set and devices will not have a specific Device Address, but will be read only via IP address. However, when I try to emulate the data changes (three different computers over a VPN, using modsim for the data) I get no changes on the animations I'm testing. I tried a P2P connection from my laptop to QP+ and still no readings. I need to test this before configuring the modbus mapping.

That's a bit more information but I'm afraid it is not enough detail for me to be of any more help.
Maybe someone else can.

On one or all three of the PCs, run WireShark to see what's happening.. ie, are the connections being opened, but no reply, or are they not opening at all? That's where I would start.

y2kmfic said:

On one or all three of the PCs, run WireShark to see what's happening.. ie, are the connections being opened, but no reply, or are they not opening at all? That's where I would start.

Click to expand...

Thanks for the reply. I'll try that.

Now, we have a new modbus map and each variable is masked on a specific bit in an analog variable. The map is something like this

dec addr bit mask descriptor
Virtual output 1 5416 15 32768 open
14 16384 closed
13 8192 alarm

And so on. Is there any way to emulate this? And how can I unmask each bit?