symbolic representation illustrates schematically the functions of a control circuit. The power lines form the sides of a ladder-like structure, with the program elements arranged to form the rungs.

Local Area Network. A network that takes advantage of the proximity of computers to offer relatively efficient, higher-speed communications than long-haul or wide-area networks.

Light-Emitting Diodes are solid-state devices that radiate in the visible region. They are used in alphanumeric displays and as indicator or wiring lights.

an electromechanical device positioned to be actuated when a certain motion limit occurs, thereby deactivating the actuator causing the motion.

said of any device or motion where the effect is exactly proportional to the cause.

A management technique applied to problems in which a linear function of a number of variables is subject to a number of constraints in the form of linear inequalities. Developed as a technique for planning the diversified activities of the U.S. Air Force, the process generates several different plans, requiring a criterion for deciding which plan is best and how to find it. Mathematically, linear programming is the analysis of problems in which a linear function of a number of variables is to be maximized or minimized when those variables are subject to a number of restraints in the form of linear inequalities.

a transducer for the measurement of force or weight. Action is based on strain gages mounted within the cell on a force beam.

The total resistance of a thermocouple circuit caused by the resistance of the thermocouple wire. Usually used in reference to analog pyrometers which have typical loop resistance requirements of 10 ohms.