favorite I have OPC server on CodeSys. I am trying to read variables using LabView.
I have tried two options:
using DataBinding to OPC Variables in controls using DataSocket Open, Read, Write, Close VI LabView returns no error. When I use data binding control it is green and the message is "Active: Connected to OPC server".
Unfortunately when I force variables in CodeSys i see no changes in LabView.
I recently was presented with the task of integrating a Mitsubishi PLC into our systems. After a good deal of googling, I think the best (maybe only) way to get the data out is going to be via OPC, thanks to their proprietary Melsoft protocol. If anyone else knows a better way, feel free to stop me here.
Now, we are currently expanding our data generating capabilities (hence the PLC), and I have been thinking about rearchitecting the way we collect data from all over our facility to be more flexible. Since I may be required to use OPC anyways, I was considering using an OPC server to aggregate all of the facility data, and then redistribute to control rooms, historical logging, etc. To do this, we would need to integrate our cRIOs and operator PCs into the OPC environment as well.
I don’t see OPC mentioned very often (in fact it returns 0 results on LAVAG), and a lot of the stuff I see these days seems to be more “roll your own” or lower level (raw TCP/UDP, 0MQ, Network Streams, Transport.lvlib etc.) rather than a monolithic abstracting bridge like OPC. Unfortunately, I won’t have time to roll my own in the near future, but LVRT supports supports OPC UA, so I could potentially integrate the cRIOs fairly easily. Unfortunately, I think I would have to use LabVIEW DSC (or datasockets...) to integrate the PCs.
I would be very grateful if anyone has the experience to comment on the following or anything else related to using OPC.
What are viable update rates for OPC tags? I will need at the very (very) least 250 ms update rates. Is OPC typically low latency (time from data generated to to client received)? Does anyone have a recommendation for a product (NI OPC, Kepware, etc.)? Is OPC still popular, or are there other options for data aggregation that would be better suited to a new application? What are the options for logging and alarming with OPC? What are the options for talking to OPC from LabVIEW? How robust are the OPC connections in regards to reconnecting if a wireless connection is temporarily lost? Thanks in advance!
Hello to all.
First I explain my environment and then I will ask the question.
PC 1 (development PC): intel i5, windows10 64bits, 8GB Ram, Labview 2015 SP1 (32 bits), Vision Adquisition Software 2015, Module Vision 2015, DSC 2015, ni OPC Server.
PC 2 (deployment PC) : intel celeron 1.99 GHz, windows 7 64bits 8GB Ram, Labview 2015 SP1 (32 bits), VIsion Adquisition Software 2015, Module Vision 2015, DSC 2015, ni OPC Server, Run Time Engine 2015, VIsion Run Time 2015.
PC 3 (deployment PC) intel Atom CPU N2600 1.40GHz, windows 7 64bits, 4GB Ram, Labview 2015 SP1 (32 bits), VIsion Adquisition Software 2015, Module VIsion 2015, DSC 2015, ni OPC Server, Run Time Engine 2015, VIsion Run Time 2015.
I use the next in my aplication:
2 cameras GigE Lan connected to PC. A PLC connected RS232 through ni OPC server and about 15 shared variables.
In development environment my application works well. In PC 2 a executable of my application works well.
But the problem is that the same executable works bad in PC 3. Front Panel is slow and displays of image cameras don't refresh the image well. So all my application is slow in PC 3.
What can it be? I don't think that it could be the specification of PC 3 but I don't know... Does anyone fix something similar?
Any help will be appreciate it.
Thanks a lot.
I have a question regarding creating reference/Variable nodes in the OPC UA Data structure. For example, we have two items in a big data structure tree having the same property, Is it possible to create this reference property while building the data structure? And can it be represented in the data tree at both items? Should I use local Variables for this task? and how?
In short, Iam asking if its possible to have same property represented two times in the Data tree and when we change it's value in one place, it automatically changes in the other place.
Any advice would be highly appreciated. Thank you.