Node-Red msg.payload is reported under a different title

I have a problem that I can not figure out;

If I look in a debug view, no matter where the msg.payload is reported constantly from a different source. The reported value is correct though, so it is not a real problem but I can not figure it out what the reason is. If you put the debug later in the flow it correctly reports for instance 381 (watts) but alternating between Solar_Amps and Solar_Voltage (se second screenshot.

It seems it keeps propagating the value as it is triggered and then randomly assign the title as it is received? Is this controllable?

In my case The amps and voltage are reported, joined and multiplied.

That is expected behaviour. It “merges” the current message, with the old messages based on topic.

You can set the debug to the entire message, not just the payload to better understand the shape

Yes, I understand, but does this also explain the second screenshot?

I’m not sure how it decides where the origin of a message is. In my case, it seems it is the last input or change node. Not sure why the function node is not recognised in that case.

What happens if you use a change node instead of a function? JSONata of msg.payload.Solar_Amps * msg.payload.Solar_Voltage