For my first project in KiCad, I’m making a simple control panel that I can use in my workshop to turn on and off power to 4 devices. (These are connected to an ESP32, so it’s more than just turning them on and off with a switch.) I have switches that are DPST and some optocouplers. I’d like to indicate the switches are DPST and to include that on the schematic as well as the optocouplers. The problem is the devices on the output side of the optocouplers and on the 2nd pole of the switches are off the board and I don’t want to include them in the schematic. I’d rather just have some kind of flag or arrow and label it something like, “To laser control,” or, “To etching laser.” True, both are loads, but their power source is external to my circuit and so is the load for that power.
How would I indicate that in a KiCad schematic so they don’t get flagged as errors? (I get that for a foot print, I can use something like molex pins for connectors, so I see how that works, but I’m not sure about what to do about the actual devices.)
You can’t just have a “flag” for off-board things, you need to represent what you will have on that PCB… so a connector… (which you can put useful words next to). If you just want some PCB holes you can solder wires to, then use something like “Connector pin socket” or “Connector pin header”… so a row of holes that you COULD fit Molex pins to… or just wires.
If you are just using the schematic to document something, then it doesn’t really matter what you do!!
You’d have to connect your external devices in some way to the PCB, and the most logical is to add a connector on the schematic and on the PCB.
For the rest, I do not understand. You have some devices (your switches or optocouplers?) that are not on the PCB, and you don’t want them on the schematic either, so where do you want to put them?
Maybe you could give us a visual help, a photo, a 3D model, or pencil drawing as an example. I don’t understand either what you are doing.
Are the optocouplers etc. completely in this board? If yes, how are they connected to the external something (“off the board”)? Or is the output side of the optocoupler component in the other board, for example so that the component crosses the edges of two boards, one side being attached to one board and the other side to the other board?
Well if they are not part of the board, then the components can’t be represented on the schematic as symbols. Maybe you could import a graphics object to the schematic that depicts the external components. That object could be generated from a separate schematic that isn’t used to make a board, i.e. a separate project.