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Version: 24.2 (stable)

PLC Connections

Manual Configuration​

Use Manual Configuration as Last Resort

Manual settings should only be used as a last resort, e.g. when…

  • …specific configurations are needed to make connections to certain PLCs work
  • …configuration of these features are not yet possible via the IDE

Please be aware that the stability of manual configurations may not be guaranteed when upgrading to new versions of HELIO.

Options for Restricted & Limited PLCs (OPC-UA)​

Some PLCs provide a very limited OPC-UA API to ensure they fulfill their main tasks. Unfortunately these limits are often not available as OPC-UA metadata so HELIO can take it into account.

However, the OPC-UA Connection in HELIO provides the following flags to adjust the HELIO runtime to the needs of specific PLCs:

/** Maximum batch size for browsing node IDs */
maxBatchSizeBrowse: schema.number().positive().optional()

/** Maximum batch size for reading node IDs */
maxBatchSizeRead: schema.number().positive().optional()

/** Timeout when browsing node IDs (ms) */
timeoutBrowse: schema.number().positive().optional()

/** Timeout when reading node IDs (ms) */
timeoutRead: schema.number().positive().optional()

/** Timeout when connecting (ms) */
timeoutConnect: schema.number().positive().optional()

/** Timeout when creating session (ms) */
timeoutCreateSession: schema.number().positive().optional()

/** Timeout when creating subscription (ms) */
timeoutCreateSubscription: schema.number().positive().optional()

Restricting Browse Requests​

  1. Locate the Runtime Config File

Navigate to the HELIO Data Directory and open the config.json in your favorite editor.

  1. Add maxBatchSizeBrowse options
  • Locate the connections section within the file and locate your OPC-UA connection. Each connection is identified by a unique ConnectionID.
  • Add the maxBatchSizeBrowse option and provide a positive integer as its value.
{
  "connections": {
    "<ConnectionID>": {
      "$heServiceId": "com.helio-hmi.builtin.Opcua",
      "props": {
        "url": "opc.tcp://...",
        "maxBatchSizeBrowse": 20,
        "clientOptions": {
          "endpointMustExist": false
        }
      }
    }
  }
}