Solution
This is because property nodes, by default, don't know what data type you want to pass into it. You can let it know what type it is by creating a strict property node.
You do this by:
- Making sure your chart is of waveform data (pass waveform data into the indicator).
- Create a control refnum.
- Place the chart into the control refnum.
- wire that control refnum into property node, and see it add the word "(strict)".
- Now you can pass waveform data type into it.