DataItemType's [Definition] property

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j.zhou.5q
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DataItemType's [Definition] property

Post by j.zhou.5q »

Hi,

We are developing a OPC UA server. We wonder how to deal with DataItemType's [Definition] property.

In part8, the description about [Definition] is
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Definition is a vendor-specific, human readable string that specifies how the value of this DataItem is calculated. Definition is non-localized and will often contain an equation that can be parsed by certain clients.
Example: Definition ::= “(TempA – 25) + TempB”
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But if this DataItem is not calculated, it is directly sampled from device.(For example, temperature)
What should we put into [Definition]?(There is no equation, and so on.)

I am looking forward your answer. Thank you!

Best Regards,
James

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Re: DataItemType's [Definition] property

Post by Support Team »

Hi,

The Definition property is optional and is not created if there is no useful information available.

Best Regards,
Unified Automation Support Team

j.zhou.5q
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Re: DataItemType's [Definition] property

Post by j.zhou.5q »

Hi,

Thank you very much! I got it.
I think I should creat it for calculated node only.

Best Regards,
James
Support Team wrote:Hi,

The Definition property is optional and is not created if there is no useful information available.

Best Regards,
Unified Automation Support Team

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