how do i know its accurate
Accurate to what?
You've posted only a portion of a sketch - what is it supposed to measure?
could i leave it on over night , how long can it run
Yes and as long as you like.
how do i know its accurate
Accurate to what?
You've posted only a portion of a sketch - what is it supposed to measure?
could i leave it on over night , how long can it run
Yes and as long as you like.