Application of industrial control systems to a large scale cryogenic system

Fermilab successfully installed and used off-the-shelf industrial controllers and software to operate five 600 Watt, one 90 Watt liquid helium refrigerators, seven strings of superconducting magnets and three liquid hydrogen targets and other miscellaneous subsystems. The equipment is distributed over a 3 km by 3 km area. The planning, wiring installation and programming was done entirely by mechanical engineers and technicians familiar with the processes being controlled, and in conjunction with their usual jobs. No computer programmers were involved. Sophisticated control schemes such as cascade PID, adaptive gains and automated quench recovery were employed on the Moore Products APACS and Siemens/TI controllers. Intellution FIX DMACS software running on PCs (with a Windows platform) provides alarming, data logging and interactive customized graphical displays of the processes for operators, engineers and managers. From any of 20 FIX DMACS nodes operators can change set points or other parameters on any of the subsystems. The FIX DMACS nodes communicate to each other over Ethernet using TCP/IP protocol and potentially can read/write to any other parameter in the controllers. Operational problems, operator man-hours and off hour call-ins have been dramatically reduced.