Engineering status of the W VII-AS coil system

The confinement coil system of the W VII-AS experiment was finally assembled in May 1988. After a period of field mapping operation and an additional assembly phase for the completion of the experimental equipment, the machine went into plasma operation in October the same year. Following an initial experimental period with an axis induction of B0=1.25 T (which is half of the value calculated for fundamental resonance with ECRH, 70 GHz) the machine was used for regular operation with B0=2.5 T in January 1989. An unexpected amount of movement at modular field coils of type No. 3 and a beginning damaging effect in the winding pack compound of that coil urged the users to limit the induction to B0 = 1.6 T for further operation. In the following, a summary of the predicted coil performance, the measured data, and the work intended for improvement of the coil system is given. (orig.)