I have always liked machines and after I got my Associates degree in 1980, I started working with machine control systems. Machines are polite, as they will sit around as long as they have to waiting patiently till they receive their instructions, then they will do as they are told, unlike most people. When I first started working with machine controls, I learned relay ladder logic, which is fascinating. The electrical system is divided up into individual ladder rungs that controls an output. A rung is a series of conditions called logic and at the end of each rung there is typically a coil at the far right, or this could be a timer. Relay ladder logic is like reading a book as it starts on the left and you proceed through each component till you reach the right and it also starts at the top and you proceed to the bottom.
This is also called a schematic diagram and if the Normally Open or Normally Closed contact series AND conditions and the parallel OR conditions together produce a true state, then the relay coil will energize and its contacts will change state. OK, that is probably a lot to grasp for those of you that never studied Electrical Engineering, so I will leave you with this song.
Written for Linda G. Hill’s Stream of Consciousness Saturday where the prompt is welcome.