Abstract: An apparatus for wrapping fiber optic cable around an overhead line (A), has a carriage (1) which sits on the overhead line (A) and is movable along the overhead line (A). A supply of fiber optic cable (B) is located on one side of the carriage (1) and a counterbalance (3) for the cable supply is located on the other side of the carriage (1). A gear set (4) is arranged to the fiber optic cable (B) around the overhead line (1). A substantially constant tension is applied to the fiber optic cable (B) during all modes of operation of the apparatus.

Abstract: The present invention relates to an apparatus for unwrapping fiber optic cable (B) from an overhead line (A). The apparatus comprises a carriage (1) which sits on the overhead line (A) and is moveable along the overhead line (A) and a guide arm (2) mounted for rotation about the carriage (1). The guide arm (2) performs the unwrapping action of the fiber optic cable (B) from the overhead line (A). There is also a drum (3) and drum drive means (5), the drum (3) gathering the fiber optic cable (B) which has been unwrapped from the overhead line (A). There are also a device (6) for varying the speed of rotation of the guide arm (2) with respect to the forward speed of the carriage (1).

Abstract: A sensor assembly 1 comprises an optical fibre 4 and a transducer 23 arranged to apply transverse strain to a localised portion 24 of the fibre. Birefringence effects induced by the fibre strain are remotely sensed to obtain a signal representative of the transducer input which in turn is connected to a current sensing coil 34 thereby enabling electric current in a conductor 32 to be remotely sensed. The localised portion 24 of the fibre 4 is stripped to remove an outer jacket and is embedded in a relatively rigid matrix material. Damage to the fibre and the effects of creep are thereby avoided. The resulting sensor is particularly suited to the measurement of high currents in power distribution systems.

Abstract: The connector comprises means (2) defining a bore (4) to receive a bared end portion or portions (20) of an optical fibre cable (16), the means (2) being surrounded by a body (12) of sealant material and a member (10) of heat recoverable material. After insertion of the cable or cables, (16) the member (12) is recovered and compresses the sealant material (10) into intimate contact with the means (2) and cable or cables (16).

Abstract: A support for an elongated piezoelectric pressure sensor, which is general cylindrical in shape is mounted on a hollow support member that has a thickness and strength selected to meet desired conditions. The elongated piezoelectric pressure sensor is wound in a helical depression on the exterior of the support member, and the support member in turn is filled with a potting material having a bulk modulus of elasticity selected to provide a sufficient flexibility so that the elongated piezoelectric sensing element generates signals that have a desired sign characteristic and improved acoustic response.