Abstract: A current-detection coil for a current transformer operating by the Rogowski principle has an insulating annular body made of a fiber-reinforced thermosetting plastic and manufactured as a single-piece solid body in a divisible mold. The parting line of a mold serving for manufacturing the annular body is in a flattened region on the outer periphery of the annular body and on a flattened region on the inner periphery. The annular body allows current transformers operating by the Rogowski principle to be manufactured that are capable of measuring in the entire range of currents that may occur and are resistant to mechanical and thermal stresses.

Abstract: A vacuum contactor has one connection terminal for the upper and lower end of each vacuum interrupter. At least the upper connection terminal has a metal member that is dimensioned essentially as a function of a current to be carried. A separate holder of insulating material is used to join the metal member to wall parts of an insulator body that accommodates the vacuum interrupters. In this manner, the distance between live parts and grounded parts of the vacuum contactor is increased and the reliability with respect to protecting against partial discharges and breakdowns is improved.