Retrieving a single Bacnet "Present Value" only

[Berx]

Hi,

I have a connection to a BACnet device and by using a BACnet Read-Node, I get a very lengthy reply.

However, I only need the value (in my case a room temperature).
How do I extract only the required value form the payload with all these arrays?

Your help is much appreciated, thanks.
Best regards,
Berx

[Colin]

There’s a great page in the docs (Working with messages : Node-RED) that will explain how to use the debug panel to find the right path to any data item.

Pay particular attention to the part about the buttons that appear under your mouse pointer when you over hover a debug message property in the sidebar.

[Berx]

Thanks, I was hopinh that there would be a special BACnet node available to enable me to quickly select the present value, but I'll take a deeper dice into the structures, thanks again.

[jbudd]

@Berx

I'll take a deeper dive into the structures

It's hardly complicated, the data you want is at msg.payload.values[0].value.
@Colin has shown you how to confirm that.

Use a change node to set msg.payload.

[Berx]

Thanks, that seems very simple to me and whatever does the job is just perfect - thanks again, it helps me a lot.