OpcUa_any: Difference between identification methods ‘BrowsePath’ and ‘NodeId’

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1

Hello!
Does anybody have any experience using the different identification methods ‘BrowsePath’ and ‘NodeId’?

Maybe this is something new in Automation Studio 6.

My guess is that if I select ‘NodeId’ I’m supposed to write the complete path from the root like this example from an ABB Omnicore:
/0:Root/0:Objects/3:Robots/3:OmniCore/2:RAPID/3:T_ROB1/3:GU_MachineConfig/3:GripCmd_PowerOn
But if I want to use the ‘BrowsePath’ option, what is the 'StartingNode’ and the ‘RelativePath’? I haven’t been able to find any information about this.

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Using OpcUa_any in simulation
How do I format Browse Path in Opcua_Any, using UA Expert?
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I found it in online help B&R Online Help

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Hmm… maybe you could help me understand then by using this NodeID as an example:

/0:Root/0:Objects/3:Robots/3:OmniCore/2:RAPID/3:T_ROB1/3:GU_MachineConfig/3:GripCmd_PowerOn

What is ‘starting node’ and what is the ‘relative path’ in this case?

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From these sentences:

“BrowsePath of the node consisting of a StartingNode and a RelativePath. If no StartingNode is specified, the RelativePath must contain the complete BrowsePath. When specifying a NamespaceIndex, the relative index from the namespace URIs table must be used.”

I would guess that it is up to you.

Option 1:

Starting node: “”

Relative Path: “/0:Root/0:Objects/3:Robots/3:OmniCore/2:RAPID/3:T_ROB1/3:GU_MachineConfig/3:GripCmd_PowerOn”

Option 2:

Starting node: e.g. “/0:Root/0:Objects/3:Robots”

Relative Path: the rest “/3:OmniCore/2:RAPID/3:T_ROB1/3:GU_MachineConfig/3:GripCmd_PowerOn”

But this is only an untested guess. So maybe someone else from BRCommunity can share his/her experiences?

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Also, after reading the help I’m not sure if I should add ‘&’ or not in the path.
&/0&:Root&/&0&:Objects&/3&:Robots&/3&:OmniCore&/2&:RAPID&/3&:T_ROB1&/3&:GU_MachineConfig&/3&:GripCmd_PowerOn

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Example of local variable: /x:&:&:/x:MyTask/x:MyVariable . Here is example of browse path I used in the past.

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NodeId option is way the fastest option.. Just read with UAExpert or other tool the NodeId on the top + with the nameSpaceID

ns=5;s=::Test.myStatus –> Syntax from UA Part 6: Mappings - 5.3.1.10 NodeId

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Ok. Then I was mistaken. I thought the NodeId should be the whole browse path.

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Is the ‘&’ character only required for local variables?

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Is the ‘&’ character only required for local variables?

The characters . / : ! # & are reserved. If a reserved character is used in a BrowseName ( so not in the NodeId part… ) , it must be preceded by a “&” in order to be used in the RelativePath.

The BrowseName of node on the B&R embedded OPC UA server is the default scope “::” and must therefore be specified as “&:&:”.

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I was looking for a couple of simple examples to show the difference of the ‘NodeId’ and ‘BrowsePath’ options. Here is a summarize:

NodeId is a relative path. Example from @job.franken: ns=5;s=::Test.myStatus

BrowsePath is an absolute path. Example from @kovarj: /0:Root/0:Objects/2:DeviceSet/2:X20BC008U/2:X2X/2:SubDevices/2:ST2/2:ProcessData/2:DigitalInput01

When using ‘BrowsePath’ you have the option to split the path:

  • Option 1: do not split the path:
    Starting node: “”
    Relative Path: “/0:Root/0:Objects/2:DeviceSet/2:X20BC008U/2:X2X/2:SubDevices/2:ST2/2:ProcessData/2:DigitalInput01”

  • Option 2: split the path:
    Starting node: “/0:Root/0:Objects/2:DeviceSet/2:X20BC008U/2:X2X/2:SubDevices/2:ST2”
    Relative Path: “/2:ProcessData/2:DigitalInput01”

Thank you @kovarj and @job.franken for your assistance!

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thanks for great summary, I marked it as a solution

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