An adapter assembly includes an elongated body, a switch, a sensor link, and an annular member. The elongated body includes a proximal portion configured to couple to a handle assembly and a distal portion configured to couple to a surgical loading unit. The switch is configured to be toggled in response to the surgical loading unit being coupled to the distal portion of the adapter assembly. The sensor link is disposed within the distal portion of the adapter assembly and biased toward a distal position. The sensor link is longitudinally movable between a proximal position and the distal position. The annular member is disposed within the distal portion and is rotatable between a first orientation, in which the annular member prevents distal movement of the sensor link, and a second orientation, in which the sensor link moves distally to toggle the switch.