I don't have a PSX1-AC to measure but have measured 180 w bricks as well as TMCC Lock Ons. Both open in just over 8 milliseconds which is the time of one half of the 60 hz sine wave. Thats about as fast any breaker can open at 60hz. I would expect the PSX1-AC to be comparable.
That said 100 ms is also likely fast enough since breakers protect the transformer. TVS diodes are what protect the engine and they are much faster.