Nora was using a power dampener on herself in the beginning, to trick her parents into allowing her to stay. Tht device may have other settings like power dampening dampening. From "securities" failed perspective, Nora has broken into and out of Iron Heights 50 to a hundred times, inside the limits of less than an hour. Thawn is going to die soon. That may not be his his holding cell, but his execution chamber, which is why Eobard is given the privacy to die with a little dignity.