The Gyrotron Commissioning Components (GCC) will be used to perform the commissioning and the site acceptance tests of the gyrotrons delivered to ITER.

The GCC comprise a set of transmission lines and mitre bends with an internal diameter of 50 mm and an internal corrugation compatible with the transmission of a HE1,1 mode at 170 GHz. The waveguides connect the Matching optical unit (MOU) of each Gyrotron to a calorimetric Dummy Load for the dissipation and measurement of the power produced by the gyrotron.

The set of GCC waveguides and mitre bends shall allow continuous operation at 1.2 MW power and hence have an adequate cooling system.