An interior vessel viewing system for DIII-D

It was anticipated that there could be damage to the interior walls of the vacuum vessel during operations of the DIII-D tokamak. In order to be visually inspected the interior walls for damage and to locate any debris resulting from operations, a miniature closed-circuit color-television camera system was developed. The camera system can be inserted into one of several ports of the vessel during a clean vent (i.e. vented to inert gas). The system has pan, tilt, and zoom capability and carries its own lighting. The use of this system allows a quick assessment of the condition of the vessel to be made under clean vent conditions. This precludes the need for the permit process and manned entry into the vessel, which would allow air inside the vessel. A permanent record of the inspection can be made on video tape. The design and configuration of this camera system is presented and its use as a diagnostic tool is discussed