Instrumentation and control developments in the Los Alamos nuclear test program

The United States Department of Energy contracts the Los Alamos National Laboratory to carry out a Nuclear Weapons Test Program in support of the national defense. The program is one of ongoing research to design, build, and test prototype nuclear devices. The goal is to determine what should ultimately be incorporated into the nation's nuclear defense stockpile. All nuclear tests are conducted underground at the Nevada Test Site (NTS). This paper describes the instrumentation and control techniques used by Los Alamos to carry out the tests. Specifically, the contrast between historical methods and new, computer-based technology are discussed. Previous techniques required large numbers of expensive, heavy hardwire cables extending from the surface to the diagnostics rack at the bottom of the vertical shaft. These cables, which provided singular control/monitor functions, have been replaced by a few optical fibers and power cables. This significant savings has been enabled through the adaptation of industrial process control technology using programmable computer control and distributed input/output. Finally, an ongoing process of developing and applying the most suitable instrumentation and control technology to the unique requirements of the Test Program is discussed. 2 refs.