What r the points in amps which require a increase in wire size? Isn't there somesort of chart?

I hope you aren't wiring anything in your house if you have to ask that question...

Wiring needs to be inspected and it has to meet local codes. If there were No permits if needed and no inspection and your house burns down... your insurance can legally refuse to pay off on the claim.


There is more to sizing wire for an application than load and wire size...

The National Electrical Code book is what you are looking for.

By code, the smallest branch circuit in a residence is 15 amp. This requires #14 AWG Copper.

20 amp uses #12 AWG, 30 amp uses #10 AWG.

However as Smoothy stated, there is much more to consider for example the Type of cable, number of conductors needed, temperature of the connecting points, etc.

What are you trying to wire?