  The Divertor Tokamak Test (DTT) facility, construction starting at Frascati,
Italy, is designed to test different solutions for divertor in view of DEMO. A
preliminary analysis of the error fields (EFs) assumed a simplified model of
rigid and independent displacements and rotations. A methodology based on the
first order truncated Taylor expansion has been applied, linking the
displacement parameters and the EFs within the required accuracies. A system of
in-vessel copper coils has been designed to counteract EFs and the ampere-turns
necessary to force them back within the request limits has been calculated.
Here, the details of the analysis have been provided.
