Abstract: The present invention is a device for simultaneously activating a warning device and deactivating turning rolls on which a vessel rotatably rests whenever the vessel rises off of one of the turning rolls. The device is provided with two safety switches which are positioned under and at either end of the vessel and adjusted so that a switch roller provided on a distal end of an upwardly biased switch arm of each safety switch engages the vessel, thereby causing the switch arm to move downward and thereby closing the switch. When the vessel moves upward, the switch opens. The switches are connected in a series circuit, with one leg of the series circuit supplying power to a contactor holding coil which controls a current controlling contactor in order to repeatedly make and break a circuit which supplies power to the turning rolls and a second leg of the series circuit supplying power to the warning device. The turning rolls are activated and the warning device is deactivated when all switches are closed.