off state (1) (of a thyristor)

The state of a thyristor, in a quadrant in which switching can occur, that corresponds to the portion of the characteristic between the origin and the breakover point.

(2) (of a thyristor surge protective device): The state of a thyristor surge protective device, in a quadrant in which switching can occur, that corresponds to the high dynamic-resistance portion of the characteristic between the origin and the beginning of the breakdown region.

References: 

JESD77-B, 2/00

JESD77-B, 2/00