A design diagram refers to a particular kind of circuit design that uses standard electrical/electronic symbols instead of images to show the way the circuit (or a part of it) works. Below is a typical 3-wire motor controller circuit using a typical short stop halt - start pushbutton channel utilizing a schematic diagram. (Momentary here means that the button/switch you activate will go back to its default place once you let go of it, usually by a spring that compels the button/switch to do this.)
Here is a variant of a diagram. The principal intent of this diagram is to demonstrate the logic (speaking to electric management ) of a circuit. This diagram is the one that I mostly come across in my own line of work, and it is extremely successful for troubleshooting issues or learning how a circuit works. Some frequencies are so enormous that most kinds of schematic diagrams need to be recorded in increments from book form (generally with coded numbers so information can be simpler located ). Again, here's the identical exact circuit because the first two weeks, however considering it in ladder type.
Less mess, right? I've got enough information in each of these diagrams to know just what this circuit does and also where to look for problems. Hope this helps. ( Note: don't confuse circuit or schematic diagrams with wiring diagrams; wiring diagrams will typically demonstrate pictures of components such as the pictorial, and also how the entire or portion of a circuit is wired. The distinction is that wiring diagrams generally put an emphasis on real physical location of necessary components relative to each other that essentially tell a layman exactly what to do about the wiring)
Pictorial schematic diagrams, or pictorial circuit diagrams are essentially the same thing with exactly the same function, but they use images of elements within the circuit instead of symbols. Again, here's the exact specific circuit (virtually except a controller was added and they're utilizing conductors L1 and L3 instead of L1 and L2.
Here's another schematic diagram demonstrating the same circuit, connections and components and it looks different but they fall into precisely the identical category.
Consider it in this way; a circuit diagram is any type of diagram that illustrates how a circuit operates where the principal objective is that the proper wiring of components and their relationship to each other instead of physical place relative to each other or planning prototypes. Nonetheless, in some applications classifying diagrams can be difficult so do this as general information. I've found this is particularly true when working with much more complicated circuits and electronic equipment. I'm likely to work with a simpler but typical industrial circuit since these circuit set ups are the exact same, but where it is possible to observe how each kind of diagram indicates the use of the circuit in their own ways.