A VME-based quench detection and logging system for superconducting magnets

Quench detection is one of the crucial parts in the superconducting magnet test facility, specially related to the safety issue of the measurement environment. Consequently, those old systems, mainly relying on analog/TTL gate technologies, tend to be carefully adopted with minimum modification even for a new measurement facility, to maintain the working functionality. For a new measurement environment, readjustment of the system is necessary to control the different noise environment, and to incorporate the new measurement system configuration. For this purpose, an understanding of the physics of the quench-induced signals and noises is recommended to customize a new system. We have recently developed a prototype of the new fully digital quench detection system for the Magnet Test Lab. (MTL), Superconducting Super Collider (SSC) Laboratory, based on five out-of-shelf VME cards supported by a real-time O/S VxWorks. The new digital system not only provides improved signal processing and additional logging functions, but also supports user-friendly interfacing of parameter control and status display. One demonstration shows the modularity, simplicity, versatility, and compatibility of the new with the existing systems. This paper describes the overall system design, with the development and test environment