Why would an extension cord that is too small in gauge (and thus draw less current) cause an over-current-based circuit breaker to pop? The device at the end of the cord would see a lowered voltage due to current-limiting, and the cord would likely see resistive heating.Are you using an extension cord to plug in? The extension cord must be a heavy gauge wire cord or it wlll pop the breaker. Don't use a small, wimpy, Christmas light extension cord.
Am I missing something?