Clearing chart problem

[xfear1]

Hello!
I want to clear my chart at midnight, how can I do that?
I saw there is a command in the chart help saying this:

Inputting a msg.payload containing a blank array [] will clear the chart.

But I am kind of new with node-red and don't know how to do it. Can anyone help me?

[jbudd]

An inject node can be set to inject at a specific time. To inject an empty array use the JSON inject format with [] in the field.

[xfear1]

It did work, thank you!