The 'guts ' of a USB power adapter It surprised me how small the 110v input wire is

[G+_Robert Hafer]

The 'guts' of a USB power adapter. It surprised me how small the 110v input wire is.

[G+_Tim D]

Voltage is not the problem these are at most likely rated at 300v what you want to worry about it the current flow through thin wires.

[G+_William L. DeRieux IV]

Robert Hafer

Tim D

I think, In most power supplies, the current draw from the AC side is very low (say 700 mA to 1 A) and they are often smps (switched-mode power supplies).

 

I found a chart of wire sizes and the current draw they can support.

http://hyperphysics.phy-astr.gsu.edu/hbase/tables/wirega.html

 

A single solid core copper wire (AWG 24) can handle a maximum of 3.5A.

AWG 22 = 7A.

 

The red positive wire looks like it is either AWG24 or AWG 22 and the reason why they chose this wire is probably because the wire is rated for more current than the device will actually draw from the AC side.

 

When engineering something it is always a good idea to add, say, 125% to the rated components used -- that way if there were some defect or environmental issue we would have some head room for protection.

[G+_David Wiggins]

That chart is a beauty. It goes into my collection of references