Hello all,
My lab is using a Honeywell 2182 UDA to interface with a Durafet pH probe. The UDA is connected directly to a Windows 7 PC via an ethernet cable, and we view the outputs (Temp, pH) via a Modbus server in Distributed Systems Manager, from which we can pull shared variables into Labview code.
It's a finicky setup, and we've only had sporadic success. The most difficult factor is trying to help NI-MAX establish a VISA connection to the device via entry of a raw socket IP address and Port Number. This, mind you, is darn near impossible. Finding the right combination of IP, port number, DNS server, etc. is a nightmare. On the few occasions we've done this, I've been able to get my data to work with my VI in Labview without a hitch. Until today, that is.
Tech support from my university was able to help me find the correct IP subnet to use, and then assigned the computer and device to the same subnet while varying the last octet of the IP address (192.168.1.1 for the ethernet adapter on the PC, 192.168.1.254 for the device). That worked fine: NI-MAX established a connection, I set up the Modbus, imported the variables into my project, and all was well with the world, until after about 45 hours, the connection cut out, suddenly, while I was running my VI. I wasn't touching the computer at all, just watching the block diagram while the bits flowed through my code. My PI had checked DSM every few hours since the connection was made, and we were still getting pH and Temp data.
Pinging the IP address from CMD doesn't do anything, nor does typing the IP in a browser window (another way to view data). I'm at a loss here, and hoping anybody can help.