The power unit drives the reel through an irreversible worm and wheel transmission which is totally enclosed and lubricated for life. The reduction ratio of the gearbox is fixed and rotational speed of the output spindle is selected by fitting a motor of appropriate speed. Since the motor mounts are designed to accept universally available stock motors, variation in reeling speed are easily obtained. In all cases, rotational speed of output spindle is arranged to be in excess of that required for cable reeling which ensures correct cable retrieval under all operating conditions. The energy dissipating capability of the torque controller unit, is greater than the energy permissible through the gearbox thus ensuring adequate safety margins are supplied to torque controller unit.

The power unit drives the reel through an irreversible worm and wheel transmission which is totally enclosed and lubricated for life. The reduction ratio of the gearbox is fixed and rotational speed of the output spindle is selected by fitting a motor of appropriate speed. Since the motor mounts are designed to accept universally available stock motors, variation in reeling speed are easily obtained. In all cases, rotational speed of output spindle is arranged to be in excess of that required for cable reeling which ensures correct cable retrieval under all operating conditions. The energy dissipating capability of the torque controller unit, is greater than the energy permissible through the gearbox thus ensuring adequate safety margins are supplied to torque controller unit.