Hello guys,

I need a quick help in understanding from you as I'm in the process of assembling a machine for use in the US.

NEMA 5-15 Outlet with 15Amp breaker - OK.
NEMA 5-20 Outlet with 20Amp breaker accepts both 15Amp and 20Amp plugs.
If now a 5-15 extension cord with multiple outlets is inserted into the 5-20 Outlet, can't the cord be overloaded? Because the breaker rating is too high?

Thanks,
Andy