A vacuum circuit interrupter integrates a solenoid core within the vacuum chamber for opening the separable contacts under non-fault conditions, using less space than if the solenoid were disposed in series with a high speed actuator. The interrupter includes an iron core, a steel seat with a trough, and a solenoid coil seated in the trough. The steel seat has a central opening through which the movable conductor passes. The iron core is fixed to a portion of the movable conductor so as to laterally surround the movable conductor within the vacuum chamber. The steel seat is structured such that, when the separable contacts are closed and a user provides an activating current to the solenoid coil, the magnetic field generated around the coil magnetizes the steel seat. When the steel seat is magnetized, it attracts the iron core, causing the movable conductor to separate from the stationary conductor.