[en] The physical goals and principles of helical magnetic limiters are described. They are used to develop design criteria for modular structures of helical conductors, which are then applied to a special case (TEXTOR). A 1-dimensional transport code is used to predict the plasma-parameters for the helical magnetic limiter case. These calculations show a substantial reduction (as compared to a normal limiter case) of the temperatures in the plasma boundary, while the plasma density there stays sufficiently large. (orig.)