The great advantage of having an automated valve is that it can be remotely controlled. This means that operators can sit in a control room and control a process without having to physically go to the valve and give it an open or close command, the most basic type of control for an automated valve. The ability to remotely control a valve is easily achieved by running a pair of wires out to the actuator from the control room. Applying power across the wires can energize a coil, initiating motion in an electric or fluid power actuator. Positioning a valve in an intermediate position can be done using this type of control. However, feedback would be needed to verify the actuator is at the desired position. A more common method of positioning an actuator is to feed a proportional signal to the actuator such as 4-20 mA, so that the actuator, using a comparator device, can position itself in direct portion to the received signal.