[cesarb]

> Having enough inrush current to trip a breaker doesn't seem so terrible or entirely unexpected

It should still not happen, since breakers are supposed to deal with inrush currents. A quick look at a random circuit breaker manufacturer page tells me that this particular breaker model is meant to instantly trip once the current is 3 to 5 times larger than the nominal current; less than that, it should take several seconds to trip, giving enough time for the inrush current to cease. So either the breaker (and the wiring) is underdimensioned, or the device is using too much power.

(IIRC, the trick is that most breakers have two independent trip mechanisms: a thermal one which has a built-in heat-dependent delay, and a magnetic one which is instant.)

[rootusrootus]

Right, I don't think inrush should pop a breaker, and I'd replace that breaker to see if it's just got an over-sensitive magnetic trip (IME they get more and more sensitive the more they pop). But it's a safe failure, at least. If the thermal breaker isn't working, that's dangerous.

[weaksauce]

> (IIRC, the trick is that most breakers have two independent trip mechanisms: a thermal one which has a built-in heat-dependent delay, and a magnetic one which is instant.)

precisely it. the magnetic one uses the fact that ac makes an electromagnet and they tune it so it snaps away quickly if there's a short.

[calvinmorrison]

Right isn't that a time delay fuse is used for?