The ITER bolometer diagnostic is planned to have 550 lines of sight (LOS) distributed all over the vessel. 240 channels are provided by cameras mounted in two Upper Ports and in one Equatorial Port. This paper describes the current status of the system level design of the port cameras and the solutions proposed on how to implement all required camera components while meeting a multitude of competing requirements. Sensor holders, support structures and different apertures depending on the camera type (pinhole or collimator), cable connectors, ceramic track plates and many mineral insulated cables have to be integrated within a restricted space envelope to guarantee functionality. The design of the internal electrical interfaces and the external mechanical mountings will be described as well. Using the example of an Upper Port camera with 60 LOS, the assembly of the camera components is explained and two currently discussed architecture options for the remote handling maintenance scheme in the hot cell are compared.

The ITER bolometer diagnostic shall provide the measurement of the total radiation emitted from the plasma, a part of the overall energy balance. Up to 550 lines-of-sight (LOS) will be installed in ITER observing the whole plasma from many different angles to enable reliable measurements and tomographic reconstructions of the spatially resolved radiation profile. The performance of the diagnostic is intimately linked to the constraints imposed by the design requirements, the sensor and data acquisition design, as well as expected noise levels.The results presented contain the estimated signal intensities for the current design and integration of bolometer cameras in ITER, based on the simulated radiation profile for the ITER standard scenario (DT-plasma at 15 MA, 500 MW with low impurity content). The corresponding power deposited onto the absorber ranges between 0.5 µW and 2 mW. The expected noise levels derived mainly from lab measurements and compared to operating bolometer systems yield estimated values for ITER in the order of 1 µW, clearly indicating a need for optimizing the diagnostic.The optimization potential is discussed. Cameras for which the light yield could be increased are identified. Also, the potential for enhancing the sensitivity by using different absorber thicknesses is explored.