How can this sink thousands of amps, if connected via a 20A breaker as recommended? Wouldn't a large surge trip the breaker, and thereby effectively disable the surge protection?

Chuck, I was thinking the same as you, and the response was less than expected. My thought is, if you're going to put this on dual 20a breakers, the 25-kA, or 50-kA will trip the breaker just as fast as this more expensive device, so what does the more expensive device do to justify its expense?

Hi chuck, HEPD80 is a surge protection device and this provides over Voltage protection and not over Current protection. The large amperage seen here (80kA) is the amount of current that the device can handle or the amount of current that can safely pass through the device without the device being destroyed or failing. Warm regards, Schneider Electric Customer Care.