Abstract: A device to prevent the theft of electrical appliances in which the electrical plug of the appliance is plugged in and secured within the device, thereby making the device an integral part of the appliance. The device is plugged into a wall outlet or power strip and the power is connected directly to the appliance. The device incorporates an internal power source, such as a battery, and an alarm connected in series so that the alarm will be activated if the device is unplugged from the electrical outlet. Since the device is securely attached to the appliance it will discourage an attempt to carry it away.

Abstract: A method and apparatus are disclosed for controlling the wheel slip of an electric or diesel electric locomotive such that optimum wheel adhesion may be attained. A certain characteristic of a series traction motor, specifically the back emf per rpm versus motor current (E/n vs. I), forms the basis for a voltage control which limits the voltage (V) supply to each motor to a value which will limit the maximum percentage wheel slip. The selected limit value of wheel slip is great enough to encompass the conditions of maximum adhesion under most rail conditions. By combining the E/n with the motor IR drop, motor current, and a locomotive speed signal, the idealized voltage V for a non-slip condition is derived. This voltage is increased by a factor representing the desired maximum percentage slip to obtain the limiting voltage which may be supplied to the motor.