Suppose I have a PV panel. On it's peak time it produce 7 A with 14 V. So to find out how many watts I get from it I would simply apply this formula:
\$P = I \cdot V\$
So, by applying above formula:
\$ P = 7~A \cdot 14~V = 98~W\$
So, I would get 98 Watts of power, right.
Now, If I calculated the power coming from my wall socket by this same method, I could easily measure voltage but when measuring current, the short circuit will cause (because resistance of ammeter is very low) and BOOM! (I think so, this will happen). As current from PV was pretty less than the current from outlet so I assumed it would be safe.
So, basically my question is that there are standard 220 V in my wall socket, how much maximum current can I get from it?
Mentioning of 220 V reminded me that some countries have 110 V house supply. What is the reason for it? What's the benefit of having 220 V over 110 V or 110 V over 220 V?