Author Topic: Need a tutorial on True False  (Read 4916 times)


  • Newbie
  • Posts: 2
  • I'm a llama!
    • View Profile
Need a tutorial on True False
« on: February 05, 2013, 12:19:18 AM »
Hi all
Trying to get my head around the basics but it seems so confusing.

My Take is:
If an I/P
X1 goes High (e.g +24V)= True
and I/P X1 is XIC (examine if closed i.e. Normally Closed)

Then surely XIC is True. Since X1 is XIC and normally closed and it is true then it is closed, because its True.

However if I/P X1 were to go Low (e.g 0V)= False, then the normally closed element X1 should therefore be open, because it is now Not True.

Is there a tutorial that brings all this together and explains it since I already have a dozen articles off the net and they seems reverse logic and contradictory to me.

Given that we are discussing Positive Logic, to keep it simple.