I mean.. it's barely a question, since I don't know what answer it could possibly be other than 'yeah'. But, whatever.
I got a Meanwell 606 arcade power supply and was surprised to see that there are 3 points (12, +5, -5) and only two common points. I'm probably not gonna use all three, but, just out of sheer curiosity... can you do that?
I mean, can +12 and -5 volts all go go the same ground? Can all three?
It's just, I'm so used to working on smaller parts where there's only ever one voltage.
Also, what's up with that ozone smell (I think it's ozone) that power supplies give of sometimes?
All those voltages should use a common ground unless otherwise indicated by a really big warning label. Conceptually, it's probably more useful to think of the ground wire as the 'common' wire instead. On the two-dimensional voltage graph, +12 and +5 chart above the common, whereas -5 charts below it. Everything should connect back up to ground again. -5V is very commonly found on arcade power supplies.
I believe the ozone smell you're describing is the layer of zinc that goes over sheet metal steel to inhibit corrosion, which is sacrificed as oxidation occurs. I'm not 100 percent sure about that one though.
Give the two commons the old multimeter beep. If it beeps, the two ports are exactly the same thing.