In this KiCad schematic, why is the power and ground are connected together?

Hey,
sorry if this seems like a stupid question but its my first time using Kicad to create a PCB.

I was following a tutorial template and in its schematic I noticed that the the +12V and -12V power sources are connected to the ground, wouldn’t that short the circuit ? I attached a screen shot of the schematic below.

Screen Shot 2020-02-20 at 12.54.50 PM

Current does not pass through the capacitor. (Well, not an appreciable amount but that doesn’t matter here.) In this case the capacitors buffer the charge potential to keep it steady. Think of them as very short term storage devices that deal with spikes and dips. Mainly dips when other devices ‘kick in’. You will find these capacitors in just about every power supply to keep the voltage steady.

Or maybe you thought that the wires crossing each other form a junction? They don’t. The dots are junctions.

Also if you thought PWR_FLAG was a label and therefore the three rails are connected, it is not. It’s a special to tell the ERC, don’t worry, this net is driven.

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thank you guys, that was very helpful.

But you made us curious: what did you think?

I thought the capacitor that are connected between the power terminal and the ground were shorting the power rail… I totally forgot that capacitor doesn’t pass current, and they are connected like that to absorb the voltage spikes.

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The capacitor does not pass DC current but it does pass AC current. The capacitor limits rapid changes in the voltage between the two points that it connects. This function is generally called bypassing, and the capacitor works as a bypass capacitor. All modern electronic systems use bypass capacitors (frequently many of them) to minimize disturbances (rapid variations) in the DC rail voltages.

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