180. As shown in the illustration, what is responsible for maintaining the «UV» relay energized when the master switch handle is moved away from the «off» position

The normally open «UV» sealing contact maintains the UV relay energized after initial activation. This contact closes when the UV relay is energized, creating a self-sustaining circuit that keeps the relay powered even as the master switch handle moves away from the «off» position. The overload contact permits current flow, while the master switch contacts provide only the initial energizing path.