opc-ua

问题 I would like to create an application for industrial automation to do the following functionalities: Read values from PLC, SCADA, and DCA Process those values and notify failures to Supervisor and Technician I am new to the Industrial Automation industry and IoT, and I knew that we have OPC UA in place to rescue. I came across many websites and youtube videos to understand OPC UA and its predecessors (OPC DA, OPC A&E, OPC HDA). And I have installed matrikon OPC server and explorer (client) to

问题 I would like to ask how should I work correctly with Struct when I am trying to read some object from opc ua server. I went trough this example and I was able to read the data. But right now I don't know how to correctly read them. Let's imagine I am reading some datastructure including two arrays for x and y values. I tried to do something like this: Float[] x = (Float[])struct.getMember("x").getValue() Float[] y = (Float[])struct.getMember("y").getValue() but I receive exception "Cannot

问题 I need to create something to read data from a PLC and write it to a SQL database. I mostly work with Siemens (and Sigmatek) and I think OPC-UA would be a good solution. My problem is that I don't know what the "right" way would be to start with this. With a PLC you sometimes come in contact with C or C++ (I always forget which one). So I think that would be a good starting point, but a good connection to an SQL-database would be very handy. That's where things gets blurry for me. In the past

问题 I need to create something to read data from a PLC and write it to a SQL database. I mostly work with Siemens (and Sigmatek) and I think OPC-UA would be a good solution. My problem is that I don't know what the "right" way would be to start with this. With a PLC you sometimes come in contact with C or C++ (I always forget which one). So I think that would be a good starting point, but a good connection to an SQL-database would be very handy. That's where things gets blurry for me. In the past

问题 I need to create something to read data from a PLC and write it to a SQL database. I mostly work with Siemens (and Sigmatek) and I think OPC-UA would be a good solution. My problem is that I don't know what the "right" way would be to start with this. With a PLC you sometimes come in contact with C or C++ (I always forget which one). So I think that would be a good starting point, but a good connection to an SQL-database would be very handy. That's where things gets blurry for me. In the past

问题 The problem and what I suspect goes wrong: I am trying to read a custom data type node from a Siemens Simatic S7-1500 and decoding fails with: Error running client example: max string length exceeded (length=1819042152, max=2097152) org.eclipse.milo.opcua.stack.core.UaSerializationException: max string length exceeded (length=1819042152, max=2097152) What I did so far: First of all, I've read and tried out the ReadWriteCustomDataTypeNodeExample from the client examples module. I've basically

问题 The problem and what I suspect goes wrong: I am trying to read a custom data type node from a Siemens Simatic S7-1500 and decoding fails with: Error running client example: max string length exceeded (length=1819042152, max=2097152) org.eclipse.milo.opcua.stack.core.UaSerializationException: max string length exceeded (length=1819042152, max=2097152) What I did so far: First of all, I've read and tried out the ReadWriteCustomDataTypeNodeExample from the client examples module. I've basically

问题 The problem and what I suspect goes wrong: I am trying to read a custom data type node from a Siemens Simatic S7-1500 and decoding fails with: Error running client example: max string length exceeded (length=1819042152, max=2097152) org.eclipse.milo.opcua.stack.core.UaSerializationException: max string length exceeded (length=1819042152, max=2097152) What I did so far: First of all, I've read and tried out the ReadWriteCustomDataTypeNodeExample from the client examples module. I've basically

来源： https://stackoverflow.com/questions/58305886/how-do-i-reliably-write-to-a-opc-ua-server

问题 I would like to know if I can send data from an OPC UA Client to Server. I have a Windows 10 PC with OPC UA Server set up and some Raspberry Pi as Clients. I already programmed Python code to send data from Server to Client. Now, I want to send data from the clients on Raspberry Pis to the Server on Windows 10 PC. Can this be done? Or will I have to set up the servers on Raspberry Pis, and clients on Windows 10 PC? This the server.py : from opcua import Server from random import randint