Cable winch

A cable winch adapted to deploy and retract a cable during installation of powerline cables on transmission towers, the winch comprising:

• a base frame;
• a spool mounted for rotation on the base frame, the cable being releasably securable to the spool and extending through the cable winch along a cable path;
• a drive system connected to the spool and able to drive rotation of the spool to either pay out or wind in the cable along the cable path;
• a sensor system arranged on the cable path through which the cable passes downstream of the spool, the sensor system having:
• a first sensor able to detect and output tension data in relation to tension in the cable passing through the sensor system;
• and
• a second sensor able to detect and output speed data in relation to a speed of the cable passing through the sensor system;
• and
• a control system adapted to receive the tension data and the speed data output by the sensor system and modulate a speed and a torque of the drive system in order to maintain a predetermined tension in the cable and/or a predetermined speed of the cable passing through the sensor system,
• wherein the sensor system includes a sensing sheave associated with the first sensor, the cable passing through the sensing sheave and exerting a force on the first sensor,
• wherein the sensor system includes an inner alignment sheave upstream of the sensing sheave and an outer alignment sheave downstream of the sensing sheave, and
• wherein the cable path between the inner alignment sheave and the sensing sheave is parallel to the cable path between the outer alignment sheave and the sensing sheave and is also perpendicular to an axis of rotation of the sensing sheave.