At the outset let me confess that I am very very new to PCB design & KiCad.
Please help me,out.
I am designing a Schematic on Arduino Home automation, which needs two separate power supply and Ground.
Is there any option I an place 2 separate VCC & 2 separate GND, both of same voltage(5 VDC)
Thanking You
Yes, of course you can use multiple power supplies on a PCB, and separate GND nets. You just have to make sure to use different names for the nets. To make this easy there are several predefined power symbols.
Just press p in Eeschema to add a Power symbol and then choose one of these 101 symbols.
I also recommend to draw your schematic and PCB in stages.
First draw a part of your schematic, and make a preleminiary PCB from that part, then add some parts to the schematic and add those parts to the PCB.
Doing this in stages gives you a much clearer idea of how the internals of KiCad work and when nets get connected to each other.
Are you saying that the two halves of the circuit are isolated? Do you have a means of transferring the signal like an optocoupler or a transformer? Otherwise you will need a common ground, even if they are supplied by separate power supplies. Are you able to post your schematic?
And how with electronic at all?
Are you also new, or have some experience?
Are you sure you need separate GND and VCC?
How you get these two isolated one from another power supplies?
You have two separate supply units or you have the isolated DCDC converter on board?
I just don’t know Arduino. Typical pcbs for amateurs don’t have isolation. But as it is for home automation it can have it.
Thanks a lot for the Support.
Thanks for your prompt support.
Sir since I am a new user I can’t attach anything still trying to do for your reference.
Yes I need separate GND & VCC & the two supplies are isolated using PIC 817.
Sir I am a learner, always new to this vast ocean.
Ok but you really don’t need the optocoupler as the relay is isolation, even though you have drawn it like the low voltage and AC sections are intertwined. Hint for drawing circuits even by hand, place higher potentials higher up, not with VCC pointing down as you have it. If you did that it would be obvious that the suppression diode is the wrong way around. And don’t draw a connection through the coil.
You need not to use “Sir”.
Here we are all equal.
In my opinion, at your picture the dashed line (I understand it as information about galvanic separation) should pass through the optocoupler.
I think that if you could add that hand-made picture you could probably also add the screen-shot from KiCad schematic.
And as you were already told if you use enough good (in sense of isolation) relay you will not need two separate power sources. I am not using relays to drive AC load so can’t point exactly which one is enough good (save).
It’s a cultural habit. I think I can guess where OP is located. 
I think cultural + age.
I suppose OP is young, so used to say to others that way. Of course, I’m not sure.
Just wonted to make him feel here more comfortable.
Leveled up. Attach away.
What sort of things do you want to switch with the relay, and what sort of relay do you want to use for it?
I’m always a bit apprehensive with the combination of a beginner in electronics and mains voltages. One of the problems is that even if “250Vac” is printed on the relay, that does not mean there is a save isolation between the coil and the contacts, but it just means the contacts are capable of switching 250Vac. Combined with beginners (which tend to get cheap stuff) and Chines shops (which sell anything they can) it’s not a good combination.
I also don’t think you need a optocoupler and separate Vcc voltages.
First off the Arduino has a few 5V pins but they are all really connected together so there is a single supply.
You should have no problems driving the transistor directly from the I/O pins of the Arduino. No need to isolate it.
I think that if someone is aware of the danger and is careful, that’s ok.
Electricity (220V AC) kicked me first time when I was 4 years + 4 months old 
Fortunately it was along one finger (I shorted my finger on both pins of the plug).
I’ve also survived 4 or 5 encounters with 230Vac when I was young, as most people do.
Unfortunately there is no consensus about what “being careful” means, and people without knowledge tend to over estimate their own capabilities, and under estimate unknown (or vaguely know) dangers.
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