Monitoring device secured to power distribution system conductors

Apparatus for monitoring power consumed from anywhere along the conductors in an ac power distribution system includes a housing with through passages through which the conductors extend. Toroidal coils mounted within the housing concentrically with the through passages sense the current in the conductors. Elongated electrically conductive screw fasteners threaded into support blocks mounted on a printed circuit board within the housing extend radially into the through passages to penetrate insulation on the conductors and to electrically contact and mechanically clamp the conductors thereby simultaneously providing a voltage tap and locking the housing to the conductor.