Closed circuit color video system on the TFTR machine

This paper describes the closed circuit color video system used on the TFTR machine and several of its systems. The system was installed for DT operations to enhance surveillance, and to diagnose problems such as frost, leaks, blowoffs, arcing and many other day to day operational problems. The system consists of 23 digital color cameras with pan, tilt, and zoom capability. Three portable camera carts with optical transceivers are also provided for special cases when it is necessary to have close machine views with electrical safety breaks. Primary controlling and monitoring is provided at the Shift Supervisor Station, which plays an essential role in each day's operations. Secondary control and monitor stations are located in the Laboratory Auditorium, for large screen projection, and the Visitor Gallery; in addition these two stations can operate a camera in the TFTR Control Room. The system has two types of switchers, a passive type for switching between control stations and a sequential type for switching between cameras. Modifications were also incorporated in the control drive circuits to double the acceptable neutron fluence. Degradation in camera and control performance due to neutron fluence from DD/DT operations, activation levels of the Test Cell cameras, and the cool down profile are discussed in this paper. The system maintenance, repair, camera replacement frequency, and the possibility of improving camera longevity by selection of parts, shielding and CCD cooling are also discussed.