Post by eschwellinger on Server not adding PLC ^{CODESYS Forge talk (Post)}
which plc type do you try to add? Unique serial numbers of the plc are mandatory too.
Last updated: 2025-02-17

Post by pilouuu on problem OPC UA array ^{CODESYS Forge talk (Post)}
Hello, why can't I read the arrays on my PLC's UA OPC server with codesys, even though they are accessible from UA Expert?
Last updated: 2025-02-26

Post by pilouuu on problem OPC UA array ^{CODESYS Forge talk (Post)}
Hello, why can't I read the arrays on my PLC's UA OPC server with codesys, even though they are accessible from UA Expert?
Last updated: 2025-02-26

Post by trebbia92 on Exception when OPCUA datasource disconnects from Server ^{CODESYS Forge talk (Post)}
I have the same issue, after disconnecting->reconnecting ethernet for 5/10 times it goes in exception.
Last updated: 2025-03-20

Post by anooyoung on OpC UA server on Raspberry Pi MC SL - Certificate Issue ^{CODESYS Forge talk (Post)}
hi, having the same issue, did you find a resolution?
Last updated: 2025-05-23

Post by eschwellinger on Licensing info not available. ^{CODESYS Forge talk (Post)}
you could add the ip of the license server by the deploy tool https://content.helpme-codesys.com/en/CODESYS%20Control/_rtsl_license_controller_linux.html
Last updated: 2025-09-29

Post by eschwellinger on File transfer via visu and codesys automation server ^{CODESYS Forge talk (Post)}
Hi, this will be possible with 1.33.0.0 release! Regards Edwin
Last updated: 2024-03-07

Post by mos89p on Codesys Soft PLC OPC UA server ^{CODESYS Forge talk (Post)}
Hi did you check the log of OPCUA expert Client?
Last updated: 2024-06-27

Post by annd on Migration von "CODESYS Control for PFC200 SL" zu WAGO FW26 "CODESYS V3.5.19.2" ^{CODESYS Forge talk (Post)}
Ich hab's hinbekommen: Nach dem Controller Update hab ich ein neues Projekt gemacht und nur den PFC200(8212) eingefügt (es erscheint dann ein leerer Kbus und eine serielle Schnittstelle COM1). Dann hab ich mich am Controller eingeloggt und den Kbus (Rechtsklick: Geräte suchen) mit allen Modulen automatisch ergänzen lassen. Bei den leeren Modulen hab ich dann das E/A-Abbild in csv exportiert. Dasselbe hab ich bei meinem alten "PFC200 SL" Projekt gemacht. Und dann in Excel alle Variablennamen in die leeren csv kopiert und danach wieder im neuen Projekt importiert. Dann hab ich noch alle Programmblöcke, Tasks, Visualisierungen und auch Modbus TCP Master u. Slave und auch Modbus COM Port Master und Slave in das neue Projekt kopiert. Weiters hab ich alle notwendigen Bibliotheken im Bibliotheksverwalter eingefügt. Dann noch ein paar kleine Fehler korrigiert (ich musst einen anderen Block zum Lesen der Uhrzeit nehmen) bis ich das neue Projekt fehlerfrei übersetzen konnte. Dann konnte ich es auf den Wago Controller übertragen und direkt starten. Es sieht so aus, dass alles läuft. Gruß annD
Last updated: 2023-11-18

Post by jari-koivuluoma on Problem trying Net Base Services 3.5.15.0 TCP connection ^{CODESYS Forge talk (Post)}
I have a need to send messages between 2 PLCs and I cant use network variables (because of size limit) so I tried writing this simple test program. This seems to work fine. I can send messages back and forth when a first "Start server" and then "Connect client". See the attached image. However, if I disconnect the client by setting ClientConnect to false and try to re-connect then the TCP_Client just gives me TIMEOUT error. When I stop and start the server again, then Im able to reconnect. How is this supposed to work? Why reconnecting wont work. There is not other way of disconnecting the client than setting xEnable of the TCP_Client to false. This is just a testing program and I will try it on 2 seperate devices once this works. PROGRAM PLC_PRG VAR CONSTANT mySize : UDINT := 255; END_VAR VAR Server: NBS.TCP_Server; ServerIpStr: STRING := '127.0.0.1'; ServerIP: NBS.IP_ADDR; ServerPort: UINT := 50000; ServerConnection: NBS.TCP_Connection; Client: NBS.TCP_Client; ServerRead: NBS.TCP_Read; ServerWrite: NBS.TCP_Write; ServerSend: STRING(mySize); ServerReceive: STRING(mySize); ServerConnect: BOOL; bServerSend: BOOL; IP: NBS.INADDR; ConnectedClientIP: STRING; ClientPort: UINT := 50000; ClientIpStr: STRING := '192.168.1.49'; ClientIP: NBS.IP_ADDR; ClientRead: NBS.TCP_Read; ClientWrite: NBS.TCP_Write; ClientSend: STRING(mySize); ClientReceive: STRING(mySize); ClientConnect: BOOL; bClientSend: BOOL; Error: BOOL; Message: BOOL; END_VAR // Server ServerIP.sAddr := ServerIpStr; Server( ipAddr := ServerIP, uiPort := ServerPort ); ServerConnection( xEnable := Server.xEnable, hServer := Server.hServer, ); IP := ServerConnection.IPAddress; ConnectedClientIP := F_Concat7( BYTE_TO_STRING(IP.S_un_b.s_b1),'.', BYTE_TO_STRING(IP.S_un_b.s_b2),'.', BYTE_TO_STRING(IP.S_un_b.s_b3),'.', BYTE_TO_STRING(IP.S_un_b.s_b4)); ServerRead( xEnable := ServerConnection.xActive, hConnection := ServerConnection.hConnection, szSize := SIZEOF(ServerReceive), pData := ADR(ServerReceive) ); IF ServerRead.xReady AND ServerRead.szCount > 0 THEN Message := TRUE; END_IF IF ServerRead.eError > 0 THEN Error := TRUE; END_IF ServerWrite( xExecute := ServerConnection.xActive AND bServerSend, hConnection := ServerConnection.hConnection, szSize := LEN(ServerSend)+1, pData := ADR(ServerSend) ); IF ServerWrite.xDone THEN bServerSend := FALSE; END_IF IF ServerWrite.eError > 0 THEN Error := TRUE; END_IF // Client ClientIP.sAddr := ClientIpStr; Client( xEnable := ClientConnect, ipAddr := ClientIP, uiPort := ServerPort, udiTimeOut := 10000000 ); ClientRead( xEnable := Client.xActive, hConnection := Client.hConnection, szSize := SIZEOF(ClientReceive), pData := ADR(ClientReceive) ); IF ClientRead.xReady AND ClientRead.szCount > 0 THEN Message := TRUE; END_IF IF ClientRead.eError > 0 THEN Error := TRUE; END_IF ClientWrite( xExecute := Client.xActive AND bClientSend, hConnection := Client.hConnection, szSize := LEN(ClientSend)+1, pData := ADR(ClientSend) ); IF ClientWrite.xDone THEN bClientSend := FALSE; END_IF IF ClientWrite.eError > 0 THEN Error := TRUE; END_IF
Last updated: 2024-10-03

Post by ahuckphin on Issues with Modbus Slave with Raspberry Pi ^{CODESYS Forge talk (Post)}
codesyscontrol_user.cfg [SysCom] Linux.Devicefile.1 = /dev/ttyUSB0 portnum:=COM.SysCom.SYS_COMPORT1; **parameters are used in the python-script ** method: "rtu" port: "COM8" baudrate: 9600 stopbits: 1 bytesize: 8 parity: 'N' timeout: 1 register address for humidity: 0x000 register address for temperature: 0x001 unit ID: 1 **parameteized in the modbus-master-comport ** see attached files
Last updated: 2024-07-11

Post by nltheves on Raspberry PI4 Serial Port ^{CODESYS Forge talk (Post)}
Hi Ricardo. I was having the same problem with Codesys and a Raspberry Pi 2W while using the GPIO uart. Your post helped me a lot. Thanks! But could not understand why MODBUS parity bit makes Codesys MODBUS COM driver stopping to work after first request transmission. Did you see this @eschwellinger ? Regards, Nelson
Last updated: 2024-07-18

Post by sandro66 on Application-based license Modbus Channels ^{CODESYS Forge talk (Post)}
Hi, I imported an old project created with version 3.51.20.50 into the new version 3.51.21.20. I'm using ModbusFB.ClientTCP v4.5.0.0. Strangely, I can no longer download the project due to a licensing issue I didn't have before. The number of Modbus channels has gone from 1 to 54!, and there's no license that would work. Can anyone tell me where I'm going wrong? Thanks Sandro
Last updated: 2025-08-27

Post by bbm1995 on Security Screen - Custom Certificates for OPC UA Server? ^{CODESYS Forge talk (Post)}
Hi everyone, is it possible to use selfsigned/created certificates (eg. with X - Certificate and Key Management) as a OPC UA Server certificate in the Security Screen? As far as I know I can only upload client certificates to the PLC and move it to "Trusted", "Untrusted" and "Quarantined". Same question is on sps-forum.de
Last updated: 2023-08-23

I don't know if this is where I should ask this, but I'm trying to get a Codesys OPC UA Client set up with a Kepware OPC UA Server ^{CODESYS Forge talk (Thread)}
I don't know if this is where I should ask this, but I'm trying to get a Codesys OPC UA Client set up with a Kepware OPC UA Server
Last updated: 2023-10-19

Post by romrot on I don't know if this is where I should ask this, but I'm trying to get a Codesys OPC UA Client set up with a Kepware OPC UA Server ^{CODESYS Forge talk (Post)}
Trying to create a Data Source under Data source manager, but I'm having issues with security. I get "BadUserAcessDenied" I don't know if there is something special I need to do on the Kepware server to make this work or what.
Last updated: 2023-10-19

Post by anoori on Setting up Raspberry pi as an Opc ua Server with UaExpert as Client ^{CODESYS Forge talk (Post)}
I am trying to set up my Raspberry Pi as an OPC UA server and use UaExpert on my Pc as the OPC UA client.However, Im encountering some certificate-related errors in UaExpert: 1.Unable to get local issuer certificate. 2. Unable to get certificate CRL. 3. Unable to verify the first certificate.
Last updated: 2024-09-11

Post by anoori on setting up Raspberry pi as an opc ua Server with UaExpert as Client ^{CODESYS Forge talk (Post)}
I am trying to set up my Raspberry Pi as an OPC UA server and use UaExpert on my Pc as the OPC UA client.However, Im encountering some certificate-related errors in UaExpert: 1.Unable to get local issuer certificate. 2. Unable to get certificate CRL. 3. Unable to verify the first certificate.
Last updated: 2024-09-11

Post by rickwot809 on Codesys Soft PLC OPC UA server ^{CODESYS Forge talk (Post)}
Enabling Anonymous Login 1. Navigate to 'Device' > 'Communication Settings' > 'Device'. 2. Next, click on 'Change Runtime Security Policy'. 3. In the new window, find and check the box for 'Allow anonymous login'. After completing these steps, you should be able to communicate with the OPC UA server.
Last updated: 2025-09-11

Post by gurkan on OPCUA array max length? ^{CODESYS Forge talk (Post)}
We are using codesys 3.5.16.30 and we have a array with strings of length 5000. We are having issues subscribing to this variable from an OPCUA client. Is there any limit in the OPCUA Server in codesys for how long an array can be on the opcua server?
Last updated: 2024-02-16

Post by bryandimino on OPC Da Server Code Meter Issues after Enabling License ^{CODESYS Forge talk (Post)}
I'm trying to get the OPC server setup on my machine and currently I'm not having luck. I went ahead and got my license setup. However when I go to run WinCoDeSysOPC.exe I get an error message that I don't have the code meter licenses installed. Does anyone have any ideas on how I can fix this issue?
Last updated: 2024-05-02

Post by tcarlbom on Read tag values using external program ^{CODESYS Forge talk (Post)}
This is my first time posting in this forum and I am new to codesys. I am a fullstack developer and I am trying to figure out how the following. What would be the best approach to create a own/custom tag browser? Either directly in codesys ide or using a separate custom program (perhaps a winforms application). 1.a. Shall I parse the .project xml file to get a list of all tags in the project? 1b. Shall I use python scripting in codesys ide to get a list of tags? Once one have selected some tags. These tags shall be exposed to a python program which will be acting as a edge computer. It’s fine to be able to import a file. 2a. I found a library called codesys plchandler which (as I understand) acts a rest api server. Is this correct? If so, can I query the api from a custom python script, ie can query what tags exist in project and or read tag values? My research so far. From earlier projects I know that using opc ua would be perfect for this but from my opinion it’s bloating the plc since it’s resource intensive. So opc ua is not an option. Codesys automation server is neat. But I don’t want to rely on some cloud services and subscription based pricing. There seem to be several interesting codesys libraries like mqtt, tcp server and NVL sender which would help me expose plc tags. But all have a common problem. One have to manually write what tags which will be used in these function blocks. I want a similar experience like “selecting” tags in the opc ua or the codesys tracing, ie a tag browser.
Last updated: 2024-06-28

Post by alexgooi on Codesys OPC DA server requires more then 2 GB of ram ^{CODESYS Forge talk (Post)}
Dear Forum, We are currently running into a problem that the CODESYS OPC DA server is running out of RAM (larger than 2 GB). We have a setup of 10 Codesys controllers which features around 300.000 discoverable tags per controller. We are only interested in 10 percent of the tags to be communicated to the OPC-server, this is due to the fact the program consists of arrays of objects which on their part implements arrays of objects, simply reducing the number of discoverable tags is not an option The OPC-DA server loads all the discoverable tags, is it possible to: 1 let the OPC-DA server only load the tags that are requested by the SCADA/MES system. 2 let the OPC-DA server claim more memory. 3 run 2 OPC-DA servers in parallel? Thank you in advance
Last updated: 2024-01-25

Post by r-niedermayer on OPC UA subscriber not operational ^{CODESYS Forge talk (Post)}
Hi. As far as projects in "old version"s are concerned, these can be upgraded to newer versions at any time. To do this, the device must be updated accordingly and the copilers and library versions must be adapted. You can find instructions on how to proceed in the online help/FAQ: https://content.helpme-codesys.com/en/CODESYS%20Development%20System/_cds_changing_compiler_version.html https://content.helpme-codesys.com/en/CODESYS%20Development%20System/_cds_cmd_update_device.html See also 4.3.22.4 "How to open an Example Project" within the following pdf for more details on the single steps: https://forge.codesys.com/lib/counit/tickets/_discuss/thread/3e991befbc/ca97/attachment/Public%20FAQ-v13-20240610_075228.pdf Regaring your OPCUA connection state always showing just "DISABLED", without knowing both sides of the assembly in detail, one can only approach the problem theoretically. We can give a chekclist on how to proceed: Fist, please recheck the communication settings in the OPC UA connection function block to ensure that the server URL, endpoint URL, and other settings are correct and match the configuration of the OPC UA server. Verify that the OPC UA server is running and accessible. -You can try to connect to the OPC UA server using a separate client, such as UAExpert, to ensure that the issue is not related to the OPC UA server itself. Test the security settings in the OPC UA connection function block to ensure that the correct security policy and certificate are selected. If you are using a dynamic connection to the OPC UA server, probe that the connection settings are correctly configured and that the OPC UA client is able to establish a connection to the OPC UA server. Also, please loock into the log files for any errors related to the OPC UA connection function block, these should be listet there. The log files may also provide additional information about the issue and help you to further troubleshoot the problem. FYI - Please see https://content.helpme-codesys.com/en/CODESYS%20Communication/_cds_obj_data_source_communication_opc_ua_server.html: Her you can finde the Communication settings via OPC UA Server -> layout Browse Live Server: The client connects to the server and detects the existing variables and types. From Information Model The client reads the data structure (layout) of the OPC UA Server from the information model set here and as a result receives the information about available variables and types. A connection to the server is not required. The list contains the information models installed in the OPC UA Information Model Repository. "Read Connection" Settings from IEC Variable (option set): - The connection settings used by the device are not read here from the dialog, but at runtime from the IEC variable specified here. - For this possibility, please see the Using a Dynamic Connection to an OPC UA Server (https://content.helpme-codesys.com/en/CODESYS%20Communication/_comm_use_dynamic_opc_ua_server_comm_settings.html) The settings for the communication of a Client-data source to an OPC UA Server can also be dynamically configured from the IEC code and can also be changed at runtime. For such a purpose, a structure is available in the DatasourceOpcUAServer library (For a description of the OPC UA Server, there is one included in the standard installation of CODESYS, https://content.helpme-codesys.com/en/CODESYS%20Communication/_cds_encrypt_communication_data_sources_opc_ua_client.html)
Last updated: 2024-11-04

Post by akrawczyk on Dynamically enabling/disabling Modbus slave devices in runtime (performance issue with timeouts) ^{CODESYS Forge talk (Post)}
Hi everyone, I'm working on a CODESYS-based project running on a Weintek cMT2078X HMI with a built-in CODESYS runtime. The system communicates with multiple Modbus RTU slave devices, arranged in a cascade. The number of connected units can vary between 2 and 8, depending on the installation. Each slave has 17 Modbus channels, which are polled cyclically every 5 seconds. The issue is that when fewer devices are physically connected (e.g. only 3 out of 8), the Modbus master still attempts to communicate with all configured slaves. This leads to massive delays due to timeouts (currently 200ms per channel). For one disconnected device, that’s: 17 × 200ms = 3.4 seconds of delay per polling cycle, and this quickly multiplies with each additional missing slave. This behavior significantly degrades the system's performance and responsiveness. We attempted a workaround where we tried to trigger polling based on a variable in the PLC program, but this caused instability and even led to hardware hangs/freezes on the cMT2078X – likely due to clashes in how the Modbus polling engine and program logic interact at runtime. My main questions are: Is there a way in CODESYS to dynamically enable/disable Modbus slave devices at runtime, using a BOOL or INT variable (e.g. indicating number of active slaves)? Can devices or channels be conditionally polled or temporarily disabled without removing them from the device tree? Are there any best practices or examples for handling variable numbers of Modbus slaves in scalable systems like this? Would splitting communication across tasks or interfaces help reduce the impact of timeouts? Any advice, documentation references, or architectural suggestions would be extremely helpful. I'm looking for a robust way to dynamically scale slave polling without degrading system stability or performance. Thanks in advance!
Last updated: 2025-08-11

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