International Cable Protection Committee

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Updated Monday 29 September 2014
This Glossary is not meant to be all encompassing but is intended to give the reader an insight into the terms used by Cableships. Any comments or suggestions please E-mail the ICPC Secretary



'A' End The end of a system, block , or single repeater, into which the positive current is usually fed.
'A' Terminal Usually the Terminal supplying positive current into the cable system


'B' End The end of a system, block, or single repeater into which the negative current is usually fed.
'B' Terminal Usually the Terminal supplying negative current into the cable system.


A and K Abbreviation for 'Anderson and Kennelly', which is a resistance test on a faulty cable, made to pinpoint the fault.
Acrylic Coating The coating on the optical fibres to protect the glass.
Amplifier Used to boost analogue signals, and inserted at intervals along a cable system in a watertight housing called a 'repeater'. This term is applied to the older co-axial systems and to the more modern optical systems.
Analogue Appertaining to Coaxial rather than Optical (digital) cable systems.
Armour Wires Normally galvanised steel wires laid around the core of the cable, to provide both tensile strength and protection.
Armoured Cable Cable covered with protective armour wires. Used mainly in shallow water (up to 2000m depth) in an attempt to prevent damage to the cable by fishing gear, anchors etc. Although with the tendency of deeper fishing activities it will be necessary to increase the depth to which armouring is used.
Articulated Piping A system of articulated pipes which are fitted over cable in very shallow water (near beaches) to give further protection to that afforded by armouring.
Attenuation The loss of electrical (or optical) strength suffered by a signal passing along a cable (or fibre).


Beach Anchor Strong point, usually concrete block embedded in the ground to act as an anchor for the shore end cable.
Beach Joint The joint between the land cable and the shore end cable.
Beach Manhole Concrete vault at the top of the beach landing point used to accommodate the beach joint. Often also used to provide the beach anchor.
Bell Mouth Circular opening above the Cable tank through which the cable passes from the tank to the deck. Allows the cable to uncoil freely from the tank.
Bight Any loop of rope or cable. Often used to refer to the single loop of cable hauled on board the cable ship during a repair.
Blavier Test A resistance test taken on a faulty cable. Used to pinpoint a fault, but unlikely to be used on modern systems.
Block Seal Method of sealing the end of the cable to prevent the ingress of water.
Bow Baulks General arrangement in the fore part of the cableship consisting of whiskers and sheaves.
Bow Sheaves Large wheels in fore part of ship over which the cable is run during cable operations.
Bow Thruster Engine and propeller in fore part of the ship which can be used to push the bow to port or starboard thus enhancing the ship's manoeuvrability during cable operations , there are two types, gill, which is capable of 360 degree rotation and tunnel which is a tube in the hull of the ship.
Bow to Stern Transfer Operation in which the cable is transferred from the bow sheaves to the after cable machinery around the outside of the ship. Usually performed at the start of a lay when a previously laid end is picked up forward and then passed aft.
Branching Unit A 'BU' is associated with Optical Cable systems, and is the subsea unit used at the point where a cable system splits into two legs. i.e. the fibres are split up and may go to two terminals or to other branching units. Some branching units have the capability for switching the fibres from one leg to another.
Braze Method of joining two coaxial cable conductors, in the manner of a 'weld'.
Break Test An electrical test taken on a broken, rather than faulty cable, to pinpoint break position.
Bridging Rope Length of rope which is stoppered to the cable either side of damage so that if the cable parts at the damage during pick up, the end will not be lost. May also refer to a similar rope joining two lengths of scrap enabling them to be paid out as one.
Bumpkins Frames which extend on either side of the cableship's stern. Used to keep cable/rope clear of the propellers during transfer operations.
Buoy (Cable) Nowadays most commonly used to mark and secure cable ends.
Burial Burial of the cable under the seabed. Achieved by a number of means, plough, ROV etc.


Cable Chart Chart showing positions of all submarine cables in the area.
Cable Data Information giving the electrical, optical, and mechanical details of cable and in the case of System data, the geographical details of the system as laid. Usually given in a standard form such as a Position List, or Splice List etc.
Cable Depots Depots strategically placed around the world which store cable suitable for the systems in that area.
Cable Drum Large power driven drum used to pick up and pay out cable.
Cable Engine The cable drum and associated machinery.
Cable Mile One cable nautical mile = 6087 ft, = 1,855.32 metres.This is different from an international nautical mile which = 6080ft = 1,852 metres.
Cable Pan A portable cable storage tank.
Cable Tanks Large tanks in the ship or depot in which the cable is stored.
Cable Transporter Small portable machine with one (or more) pair(s) of cable gripping wheels which is used to move cable sort distances e.g. between tanks.
Cableship (C.S.) A vessel usually custom built to install (lay) and repair cables
Capacity Could refer to a cableship's capacity for carrying cable, or the number of channels that a particular cable system can provide.
Chain Moorings Buoy moorings consisting of chain rather than rope used on shallow water buoys.
Chain Stopper Tapered or untapered chain of high strength steel applied in half hitches to cable. Mainly used on armoured cable during recovery, or when attaching buoy moorings to the cable.
Coaxial Cable Type of cable used for Submarine systems from the 1960s through the 1980s. Now superseded by fibre optics though some systems using this type of cable are still in operation, notably in SE Asia.
Coiling Coiling cable in a tank is usually done in a clockwise direction, with conventional left hand lay armour cable. Conventional coiling starts at the outer edge of the tank and works inwards When the inner cone has been reached, the cable is taken out to the outer edge of the tank and the process starts again.
Cone Structure in the centre of the cable tank in the form of a truncated cone. It prevents the cable being stowed at less than the minimum bending radius and also holds the cable in position.
Control Joint A joint made as a check on the jointers standard of workmanship, as well as the performance of the jointing equipment. It would be closely inspected/tested.
CR. Abbreviation for 'conductor resistance' i.e. the resistance of a system or part of a system, or resistance of a length of cable or a repeater, usually measured at low currents ( 10mA).
Crinoline A movable framework around the cone which can be moved up and down to restrict the cables tendency to whip if the distance from the top of the stow to the bell mouth is too great.
Cut & Hold Grapnel Grapnel capable of cutting the cable and then gripping the cable on one side of the cut.
Cutting Drive A grappling drive to cut cable as opposed to a holding drive.
Cutting Flatfish Type of grapnel consisting of a diamond shaped plate with a prong on each side. A blade is fitted at the junction between the plate and the prong, which cuts the cable when it lodges there. Used principally in deep water where the conditions lend themselves to this type of grapnel.


Dan Buoy Small buoy used as a 'mark' buoy.
DC Test Set Equipment used for resistance & capacitance testing of cable & plant. For routine testing, fault location, and integrity testing of cables.
De-trencher Grapnel used to 'grapple' for buried cable.
Doserate Meter Equipment used in jointing to check for radiation leakage from x-ray cameras.
Double Armour Type of cable armouring used on cable system shore ends, consisting of 2 layers of armour wires.
Dynamometer Old term describing strain measuring equipment on cablegear. Now generally superseded by the term, 'Loadcell system'.


Egglink Egg shaped steel link in cable working rope & chain fittings.
Elastomer Stripper Equipment used during cable jointing operations, to remove elastomer compound from the fibres in the fibre package.
Electrodes (Conventional) 2 trailed devices used to detect a tone applied to a submarine cable from a terminal
Electrodes (Reversed) 2 trailed devices used to inject a tone into a submarine cable system, which is detected by the terminal.
Emergency Shutdown Associated with Power Feed equipment. Operated in event of danger to personnel or cable plant.
Equaliser Passive device used to match cable loss and repeater gains throughout an ocean block within an analogue cable system. Is used on both coaxial and optically amplified systems.
Equalising Strop Length of wire rope used to 'equalise' weight between 2 stoppers.


Fibre Optic Technology employed in cable systems presently being installed, being a digital medium of telecommunications utilising pulsed lasers to transmit & receive signals through glass fibres.
Final Splice Final joint in a cable system repair operation, making system viable for traffic again.
First Splice Initial joint in a cable system repair operation, to facilitate jointing of good spare cable to original 'line' cable, once the 'fault' has been cleared.
Fitting Term used to describe connecting device between 2 lengths of rope.
Flatfish Type of grapnel usually used on a sandy seabed, can be cutting or holding type.
Fleeting Knives Machinery operated to keep cable turns in correct position on cable drum.
Fleeting Rings Perform same function as 'Fleeting Knives'
Fusion Splicer Equipment used to join 2 fibres together by process of HV arc fusion.


Gantry Support structure used to transport equipment around deck and overboard/onboard or a roller trackway used to deliver cable from a factory or depot to the ships side.
Gifford A type of grapnel comprising four wide seated hooks at right angles to each other. Used on hard or rough bottoms.
Grap Rope Usually 6x3 wire core rope used for grappling.
Grap Sheet Large scale chart used to plot ships positions when grappling for cable.
Grapnel (or Grap) A hook like device used on the end of a length of rope to raise the cable to the surface.
Ground Area in which cable operations are taking place i.e. cable ground.
Ground Chain Length of heavy chain between grap rope and grapnels to keep front end of grapnel low as grapnels dragged over bottom.
Ground Rope Rope attached to cable which lies on sea bed to which buoy moorings are attached. Where a surface buoy is undesirable can be used as a grappling tail into which the ship can grapple to recover the cable without damage.


Holding Drive A grappling drive to recover cable as opposed to a cutting drive.
Housing Small pressure proof insulated tubular insert in cable containing the splices and providing electrical path for powered systems. Provides mechanical strength to protect the splices. Repeaters are also sometimes referred to as housings.


Joint The point at which sections of cable (perhaps of differing type) are physically joined to form a section. The operation of an optical joint can take up to 24 hours on optical cable.
Joint Housing or Joint Box The rigid casing which provides protection for the vulnerable completed joint.
Jointer The person who performs the above operation.
Jointing The process of joining two ends of cable together.


Knocked-up When the weight of a buoy mooring has been transferred from the buoy to the rope on the cable engines.


Lay Term used for operation of paying out cable to seabed.
Layback Distance from the stern ( or principle point of navigation ) to the position of a towed vehicle or point at which the cable touches the seabed.
Lightweight Generally deep water cable. Where the inner steel wires (strength members) are surrounded by an insulant of natural polyethylene.
Lightweight Protected (LWP) LWP cable is the same as a basic lightweight cable except it has a much thicker polyethylene coating.
Lightweight Screened (LWS) LWS cable has a metallic tube running it's core inside of the polyethylene coating to enhance fibre protection in the event of an outside coating breach.
Linear cable engine (LCE) Machine at aft end of the vessel used to bear the weight of and pick up/pay out cable. Consists of a series of wheels and tyres which grip the cable top and bottom. The more weight that is borne , the more ' sets of wheels ' are required to hold it.
Load The term used for the operation of physically taking cable onboard the vessel.
Load cell Tension measuring system whereby compression on a unit provides a scaled reading of the actual tension on a cable. Situated on dynamometer assemblies or cable engine frames.


Maul As in trawler maul. The damage sustained by a cable when it has been hit by trawled fishing gear, commonly the otter boards used by beam trawlers.
Mini System Repeatered cable systems are designed with an optimum cable length between repeaters to maximise transmission and minimise attenuation losses. A degree of tolerance is built into the system to allow for length increases due to repairs. Deep water repairs, however, may require the addition of a repeater, this would be built into a mini system with a section of cable on either end to allow a speedy repair.
Mushroom A mushroom shaped anchor which comes in various sizes and is used for anchoring buoy moorings, cable ends etc.


Normans Pad eyes welded to the upper section of cable buoys, through which the girth wire or necklace passes, or to which the senhouse slip to the moorings is attached. The buoy trailer may also be shackled to a norman, depending on the type of buoy rig.
NOTS Nominal Operating Tensile Strength. The tension that can be applied for 48 hours to optical fibre cable in suspension with a greater than 95% fibre survival probability.
NPTS Nominal Permanent Tensile Strength. The tension that can be left in optical fibre cable for it's entire life span with guaranteed fibre survival.
NTTS Nominal Transient Tensile Strength. A term applicable to optical fibre cable which gives the tension which can be applied for one hour which gives 95% fibre survival probability. Usually expressed in kilo-newtons (kn.).


OOU Out Of Use. A term used to describe a cable which is still in situ, but is no longer in service.
Optical Amplifier An optical amplifier uses Erbium doped fibre and a laser pump to amplify an optical signal. This is done without the optical signal being regenerated by conversion to an electrical signal and then converted back into an optical signal, as is the case with optical regenerators.
OTDR Optical Time Domain Reflectometer. An instrument which is used to accurately measure the various parameters: attenuation per kilometre, splice loss etc. of an optical fibre. This will allow the assessor to gauge the quality, integrity or suitability of the fibre.


Patch Panel A connector interface for cables. (i.e. electrical connectors or optical connectors)
Pipe Tracker Device for located buried submarine cable. Usually used in association with an ROV.
Plough A tool for burying cable; A plough is a passive tool that is pulled through the seabed by a ship, simultaneously with the vessel is laying cable. It cuts a small trench in the seabed and then buries the cable.
Plough Assessment Survey (PAS) A survey carried out to determine the suitability of the seabed to bury cable.
PO Pay out of cable
Post lay Inspection and Burial (PLIB) Operation to inspect and bury cable upon completion of a lay. Utilising an ROV.
Power Budgets The margin above the minimum receivers requirement to allow for system degradation of the light source or the addition of splices to repair the cable. Used in the design of optical systems to calculate the quantity of repeaters or amplifiers
Power Feed Equipment (PFE) A constant current/ High voltage power supply used to supply DC power to a submarine cable system.
Power Safety Officer (PSO) The person on the vessel, who has responsibility to the Captain for the safety of all personnel on the cableship in respect of all dangerous voltage and current used in conjunction with jointing and testing the system during repair operations.
Pre-lay Grap Run (PLGR) Route clearance of cables and debris prior to cable lay.
Preformed Stoppers Standard size wires helixes, designed to be wrapped/grip around cables, to allow transfer of weights from the cables inner wire rope to an external grip, without damaging the outer sheath of the cable. Used primarily on lightweight or lightweight screened cables
Protection Grounding Unit (PGU) Provides the earth path, in the event of a cable becoming live, during a repair on a system that has switchable branching units. It will allow the vessel to work on a faulty leg of a system without loss of traffic on the main branch. Also known as In Service Repair Equipment (ISR)
PU Pick up; Recovery of cable
Pulse Echo Fault Locator (PEFL) Sometimes known as a reflectometer, It has been designed to locate mismatch conditions (open circuits, short circuits, joints) in coaxial cable. The nature of the mismatch can be ascertained by comparing the reflected pulse with the original transmitted pulse


Re-laid A term used for the relaying or re-routing of a cable system.
Regenerator They are the individual modules that make up a repeater and restore the optical signal to its full amplitude for onward transmission down the line. Only used in long-haul systems that need repeaters.
Remotely Operated Vehicle (ROV) A submersible unmanned vehicle used to debury/ re-bury cables during a repair. It can also be used to carry out surveys and inspection of the seabed. Various types of ROV exist, primarily, CIRRUS, SCARAB, and MARLIN.
Repair Operation whereby, a submersible cable system is made operational after loss of traffic.
Repeater A device (Amplifier) for restoring a signal back to its original transmitted level, due to the losses inherent in the conductor (i.e. glass or metal)
Reverse Gifford grapnels (RG) A type of grapnel for recovering cable on the seabed.
Rider A chain which is rigged to a slip hook high up on the side of a cable buoy and the lower end is passed through the mooring ring at the base of the buoy and is shackled to a large fitting which in turn is connected to the main buoy moorings.
Rock Armour Type of armour wires applied to submersible cable in shallow water, in order to stop damage due to rocks and anchors. The outer layer of the armour wires will have a very short lay length.
Rotometer (Roto) Used as ships for measuring the movement of cable. An instrument for measuring the length of cable paid out or recovered from the seabed.
Round Bottom Grapnel (RB) A grapnel which has 5 or 6 hooks and is used for picking up cable in mud and sand when the cable is likely to be buried.


Slack Expressed as a percentage, being the extra cable length over horizontal distance required to achieve a cable route over undulating seabed so cable will lie on seabed without suspension or excess cable to achieve the design cable system length.
Spear Point Type of grapnel used in softer seabed's to achieve greater penetration for cable recovery.
Stow A term for the stowage of the cable in a cable tank.


Taut Wire Wire paid out from vessel during cable laying to give an accurate distance with which to compare cable distance to calculate and adjust slack. Now superseded by more accurate navigation systems like GPS.
Turn Over Process of moving cable section to facilitate jointing inspection/restowing or assembly of a larger system.


Underunning Underunning is the process of passing a cable over an underunning sheave at the bow to allow the vessel to move towards a fault location or cable end. This process becomes necessary to reduce the amount of cable removed during a repair when grappling has
Up Grap Abbreviation for Position and time lifting grapnel.


V sheave Type of grooved bow or stern roller sheave for cable guide, more appropriate for older, analogue cables.
Volume Indication of the cubic capacity of cable tanks and other spaces inside the vessel. Normally measured in cubic metres.


Weight Measurement of tension in cable during laying or repair operations, normally expressed in tonnes, hundredweight's or pounds.
Whiskers Steel constructed chute, situated either for'd or aft, having radius conforming with the cable minimum bending radius, used for guiding cable into and out of the vessel.
White stop Plaited length of hemp rope approx. 1.5m long used for lashing.
Whiting Chalk Applied to tarred cable to prevent it sticking to itself.
Wire Pennant Length of wire used to hang off cables and ropes when transferring them to and from cable drums. Also used in buoy rigs and for other, similar purposes.
Wrap Term describing coiling of fibres inside a joint box.


X rays Used to detect defects such as voids, inclusions and concentricity occurring in moulded joints during cable repair operations.


Yale Grips A custom made webbing stopper for use on rope and armoured cable.

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