D0 Cryogenic System Superconducting Solenoid Platform I/O

The Dzero detector is scheduled for a major upgrade between 1996 and 1999. This note describes the specifications and configuration of the physical Input/Output devices and instrumentation of the 2 Tesla Superconducting Solenoid. The Solenoid and the VLPC cryostats both reside on the detector platform and are cooled by the Dzero Helium Refrigerator. The cryogenic process control s for these two components will be an extension of the TI565 programmable logic controller system used for other Dzero cryogenic controls. Two Input/Output Bases will be installed on the Dzero detector platform near the cryo corner. These I/O bases will handle all the sensor input and process control output devices from the Solenoid and VLPC cryostats. Having the I/O bases installed on the detector platform makes the connecting cabl ing to the platform much easier . All the instruments are wired directly to the I/O base. The bases have only one communications network cabl e that must be routed off the platform to the South side of the Dzero building