STATIC VALUE, what is it?

I found in INPUT&Values a regulator named “STATIC VALUE”, it is related to a picture gauge.
can someone explain, what it is??
I add a picture…
Static value.PNG

You can use it to test your gauge without attaching it to the input.

Ah, nice…
how to activate it in other gauges?

The slider is shown on that page if gauge is not attached to any input

Ah, nice, thank you!