Systems and methods are provided for measuring electrical parameters in an insulated conductor without requiring a galvanic connection. A non-contact, electrical parameter sensor probe may be operative to measure both current and voltage in an insulated conductor. The sensor probe includes a body, a Rogowski coil coupled to the body, and a non-contact voltage sensor coupled to the body or the Rogowski coil. The size of the loop of the Rogowski coil is selectively adjustable, such that the loop may be tightened around the conductor under test until the conductor is positioned adjacent a portion of the body or Rogowski coil that includes the non-contact voltage sensor. Measured electrical parameters may be provided to a user, e.g., via a display, or may be transmitted to one or more external systems via a suitable wired or wireless connection.