How to Feed Wire Thru Articulated Wire Track

Instrument Installation and Commissioning

A. Danielsson , in Instrumentation Reference Book (Fourth Edition), 2010

38.6 Cabling

38.6.1 General Requirements

Instrument cabling is generally run in multicore cables from the control room to the plant area (either below or above ground) and then from field junction boxes in single pairs to the field measurement or actuating devices.

For distributed microprocessor systems the inter-connection between the field and the control room is usually via duplicate data highways from remote located multiplexers or process interface units. Such duplicate highways would take totally independent routes from each other for plant security reasons.

Junction boxes must meet the hazardous area requirements applicable to their intended location and should be carefully positioned in order to minimize the lengths of individually run cables, always bearing in mind the potential hazards that could be created by fire.

Cable routes should be selected to meet the following requirements:

1.

They should be kept as short as possible.

2.

They should not cause any obstruction that would prohibit personnel or traffic access.

3.

They should not interfere with the accessibility for maintenance of other items of equipment.

4.

They should avoid hot environments or potential fire-risk areas.

5.

They should avoid areas where spillage is liable to occur or where escaping vapors or gases could present a hazard.

Cables should be supported for their whole run length by a cable tray or similar supporting steelwork. Cable trays should preferably be installed with their breadth in a vertical plane. The layout of cable trays on a plant should be carefully selected so that the minimum number of instruments in the immediate vicinity would be affected in the case of a local fire. Cable joints should be avoided other than in approved junction boxes or termination points. Cables entering junction boxes from below ground should be specially protected by fire-resistant ducting or something similar.

38.6.2 Cable Types

There are three types of signal cabling generally under consideration, i.e.,

1.

Instrument power supplies (above 50 V).

2.

High-level signals (between 6 and 50 V). This includes digital signals, alarm signals, and high-level analog signals (e.g., 4–20 mAdc).

3.

Low-level signals (below 5V). This generally covers thermocouple compensating leads and resistance element leads.

Signal wiring should be made up in twisted pairs. Solid conductors are preferable so that there is no degradation of signal due to broken strands that may occur in stranded conductors. Where stranded conductors are used, crimped connectors should be fitted. Cable screens should be provided for instrument signals, particularly low-level analog signals, unless the electronic system being used is deemed to have sufficient built-in "noise" rejection. Further mechanical protection should be provided in the form of singlewire armor and PVC outer sheath, especially if the cables are installed in exposed areas, e.g., on open cable trays. Cables routed below ground in sand-filled trenches should also have an overall lead sheath if the area is prone to hydrocarbon or chemical spillage.

38.6.3 Cable Segregation

Only signals of the same type should be contained within any one multicore cable. In addition, conductors forming part of intrinsically safe circuits should be contained in a multicore reserved solely for such circuits.

When installing cables above or below ground they should be separated into groups according to the signal level and segregated with positive spacing between the cables. As a general rule, low-level signals should be installed furthest apart from instrument power supply cables with the high-level signal cables in between. Long parallel runs of dissimilar signals should be avoided as far as possible, as this is the situation where interference is most likely to occur.

Cables used for high-integrity systems such as emergency shutdown systems or data highways should take totally independent routes or should be positively segregated from other cables. Instrument cables should be run well clear of electrical power cables and should also, as far as possible, avoid noise-generating equipment such as motors. Cable crossings should always be made at right angles.

When cables are run in trenches, the routing of such trenches should be clearly marked with concrete cable markers on both sides of the trench, and the cables should be protected by earthenware or concrete covers.

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Ocean Energy

Zoë L. Hutchison , ... Benjamin J. Williamson , in Comprehensive Renewable Energy (Second Edition), 2022

8.13.8.2 Receptor responses to MRE EMF

Cable routes pass through multiple ecosystems and, therefore, EMF emissions must be considered for a variety of receptive species, taking account of the ability to detect and sensitivity to EMFs, life history and movement ecology ( Hutchison et al., 2020c). Few studies have considered the responses of receptive species to anthropogenic EMFs in situ and many efforts have focused on the individual EMF components in aquarium studies. This has led to a patchwork of information gained from a variety of methods and exposure levels, and the knowledge base for assessing the effects and impacts on receptive species is currently lacking (Hutchison et al., 2020c).

In situ mesocosm studies have shown that electrosensitive elasmobranchs respond to cable EMFs. An assessment of movement behavior in cat-sharks (Scyliorhinus canicula) exposed to a buried AC cable EMF found them associated with zones of EMF and moving more slowly indicative of foraging behavior (Gill et al., 2009). Later, a study of little skates (Leucoraja erinacea) exposed to the EMF of a buried high-voltage (HV) DC cable showed strongly increased foraging and exploratory behavior (Hutchison et al., 2020a). It is understood from aquarium-based studies that elasmobranchs (cat-sharks) were able to distinguish between AC and DC fields simulating prey bioelectric fields but not between artificial and natural DC fields (Kimber et al., 2011). Furthermore, habituation studies indicated short-term memory of experiences, but not long-term learning (Kimber et al., 2014). There is, however, presently no insight of whether these cognitive abilities to distinguish types of electric field or learn from prior experience transfers to other taxa.

The effects of cable EMF on other fish are less well understood, but efforts to understand the influence on migratory species have been made. An in situ study of migratory eels (Anguilla anguilla) found that they slowed down when encountering a HVAC cable, although they continued their migration (Westerberg and Lagenfelt, 2008). Similarly, no barrier to movement was observed in salmon smolts (Oncorhynchus tshawytscha) encountering a HVDC cable although, when the cable was energized, salmon transit times were faster and a greater degree of transit route misdirection was noted (Wyman et al., 2018). The influence of EMFs on highly migratory species is difficult to discern and multiple life-stages will need to be considered as well as secondary effects such as the risk of entanglement and artificial reefs (Hutchison et al., 2020c; Taormina et al., 2020b).

Studies have also focused on the effects of EMF exposure on invertebrate species of commercial interest. In situ studies exposing crabs (Metacarcinus anthonyu, Cancer productus) to a HVDC cable exhibited no spatial changes in their proximity to the cable relating to the EMF and no change in their catchability was detected (Love et al., 2015, 2017). However, aquarium studies of crabs (M. magister, C. pagurus) exposed to magnetic fields demonstrated changes in behavior and physiological processes (Woodruff et al., 2012; Scott et al., 2018). In contrast, in situ studies of lobsters (H. americanus) revealed subtle changes in exploratory behavior when exposed to a HVDC cable (Hutchison et al., 2020a) but aquarium studies exposing juveniles (H. gammurus) to a magnetic field gradient reported no behavioral response (Taormina et al., 2020a). These studies may highlight species-specific responses, variation in life-stage responses and/or may be attributed to different exposure types and intensities (Hutchison et al., 2020c).

These studies exemplify the variation in approaches to assessing effects of EMF on receptor species. To improve the knowledge base, studies should carefully consider the relevant receptive life stages, movement ecology and the likely encounter rate for receptive species, combined with a better understand of cable EMF properties (Hutchison et al., 2020c). There is a call for a better understanding of the effects of anthropogenic EMFs (Newton et al., 2019; Nyqvist et al., 2020). In the context of MRE, this must include the effects of static and dynamic cabling and be differentiated from other simultaneous effects of MRE (e.g., artificial reef effects (Taormina et al., 2020b)).

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Telecommunications

In Electrical Systems and Equipment (Third Edition), 1992

1.4.1 Main telecommunications room (MTR)

The MTR has a floor area sufficient to accommodate the known and future equipment. Over-provision of space is desirable because of the inability to make accurate forecasts of future requirements which in the telecommunication field are subject to continuous change. The MTR has an adjacent battery room. A typical layout of the two rooms is shown on Fig 8.1.

FIG. 8.1. Main telecommunications room — typical floor plan

The MTR has cable routes to the main cable risers and cable tunnels for access to:

•

The power station digital pair network.

•

Telecommunications cable routes to the associated 400/275 kV switching station.

•

Each of the two physically separated incoming BT cable routes.

Access for equipment and personnel into the MTR is provided by a double door. A second door is used for access of personnel and as an emergency exit. Consideration is required of the access and equipment handling facilities available on the route to the MTR double door within the station.

The environmental conditions of dust and humidity must not at the present time be less than those applicable to the Central Control Room (CCR), as specified in Specification CEGB-EES (1980), Clause 2.2, Table 1, Class B3.

The temperature of the room should be maintained within the limits of +5°C to +40°C, allowing for a maximum heat dissipation of 10 kW from the equipment in the MTR.

With modern SPC exchanges, air conditioning is provided for the MTR to give Class A conditions, i.e.:

•

Temperature limits of +18 to +27°C.

•

Relative humidity limits of 35 to 75%.

SPC exchanges which have been approved to the requirements of the CEGB General Specification for Electronic Equipment (CEGB-EES 1980), will continue to operate within Class B temperature and humidity limits but with the possible reduction in equipment timing and other minor variations in the manufacturer's specified equipment operational limits.

To supply the MTR and the associated telecommunication battery charging requirements, two alternative 7.5 kW, three-phase, 415 V AC supplies are required to feed two 6-way, three-phase and neutral distribution boards complying with CEGB Category 2 safety requirements. Each of the two battery chargers is supplied from different AC supply distribution boards.

A 110 V 50 W AC uninterruptable power supply (UPS) is required for the radio paging central control equipment.

The minimum lighting standard is 300 Lux. Emergency lighting is also provided.

MTR equipment

The equipment includes cable distribution frames, PA(B)X, UHF radio equipment, radio paging equipment, 48 V DC power supply equipment, isolation equipment for BT incoming cables, CTN equipment and grid control telecommunications equipment (for grid system control and telephony) when the latter is not located in the associated 275 kV or 400 kV switching station.

MTR 48 V DC power supplies

If Planté batteries are used, the 48 V power supply equipment comprises: two chargers, two batteries and a single distribution board. The power supply system has sufficient electrical capacity to supply the known and predicted 48 V DC requirements of the MTR. For a modern power station this would include two batteries of approximately 400 Ah each. The arrangement complies with CEGB Transmission Plant Standards. A simplified block diagram of the system is shown in Fig 8.2. The two batteries and chargers are operated in parallel. Failure of one battery or one charger will not cause a complete failure of the system. Each charger has sufficient output to meet the total battery load. The two paralleled batteries are capable of supporting the load for approximately 12 hours.

FIG. 8.2. Main telecommunications room — 48 V DC power supplies block diagram

The arrangement enables one battery and charger to be disconnected from the load for off-load boost charging. During boost charging the standby capacity of the system is halved, e.g., it is approximately 6 hours.

The 48 V positive poles of the batteries are earthed at one point, usually at the distribution board via an isolating link. An earth cable is run between the distribution board and the power station's control and instrumentation (C and I) earth. The C and I earth is also used for the cable screen earths associated with the power station multipair cable distribution system.

The Planté batteries are located in a battery room adjacent to the MTR. The room complies with the CEGB standards for battery rooms described in Chapter 9.

If recombination cell batteries are used, the 48 V DC power supply equipment is provided for each individual telecommunications equipment. A power equipment rack (PER) comprising modular rectifiers and 48 V battery units is provided ensuite with its associated telecommunications system. Each modular battery has a capacity of approximately 100 Ah. A number of rectifier/battery modules are connected in parallel to provide the required standby capacity, e.g., 12 hours for a PAX, DWTS or AWS and 7 hours for a PABX. The advantages/disadvantages of recombination cells are described in Section 1.4.4 of this chapter.

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Marine and maintenance (from inception to end of life)

John Horne , Raynald Leconte , in Undersea Fiber Communication Systems (Second Edition), 2016

17.3.4 Route engineering

The knowledge of the final planned cable route with its RPL and alter-course instructions, together with the required levels of cable and burial protection allow:

•

The final lengths of cable and their armor types to be determined.

•

The position where cable, repeaters, branching units and splices are to be laid to be finalized.

17.3.4.1 Slack planning

The installation cable slack plan uses the detailed seabed profile, the final planned RPL and the cable burial requirements to determine the actual slack that will be paid out by the cable ship, at specific points along the route. The system supplier or his marine installation subcontractor prepares this plan. The essential purpose of slack planning is to ensure that when the cable is surface laid, it follows the contours of the seabed at touchdown, without suspension and without forming loops of excessive slack. For cable that is to be buried, cable tension must be minimized to prevent the cable being pulled out of the plow trench by residual tension, especially at alter course positions, and to allow an ROV to push the cable into a trench as part of a PLIB process.

In both cases the slack planning must also determine the actual route that the cable ship must follow to enable the cable to touch down on the seabed at the position defined by the RPL. Cable does not fall directly to the bottom; it does so at a gradual rate dependent on its hydrodynamic constant, a term to be defined later. In deep water a catenary of cable, more than 20 kilometers in length, may exist between cable leaving the vessel's stern and that touching the seabed. If the cable ship alters course, then the catenary will not follow the precise track of the ship, and therefore corrections by the ship may be necessary (Figure 17.12).

Figure 17.12. A ship's track to achieve the required touchdown point.

Courtesy of GMSL.

While the system supplier provides an area slack allowance for the route, say 2–3% for LW surface-laid cable, the actual figure required will depend upon a number of factors. These include the actual seabed topology, the cable ship position and speed, the weight of the cable in water, the cable tension, whether repeater housings or splices are being launched and if burial is required, whether it is by plow or PLIB.

From this discussion, it can be seen that slack planning requires a dynamic approach, involving a large number of variables. Computer simulations now play an essential part in the planning and installation of slack, given its complexity.

The terms used during this exercise are defined as follows:

•

Cable catenary: this is not a catenary in the true sense as to achieve zero cable tension at the seabed; this must be a straight line between the stern of the cable ship and the seabed. The weight of the cable and the speed of the ship determine the angle of descent. The heavier the cable, the quicker it sinks and the steeper is the descent angle; the faster the ship, the shallower is the angle.

•

Cable laying tension: this is the cable tension that is observed at the ship after the cable-laying catenary has been set up.

•

Ηydrodynamic constant (HC): the HC for a cable relates the speed at which a cable sinks to the speed at which it is laid. In most cases it is given in degree.knots. For example, LW cable with an HC of 60 degree.knots has a descent angle of 15   degrees if the ship laying the cable travels at 4   knots.

•

Descent angle: the angle below the horizon assumed by the cable during laying.

•

Seabed slack: the value of slack on the seabed required to cater for the seabed profile and irregularities.

•

Fill slack: the value of additional slack that may be necessary to cope with changes in slope on the seabed.

•

Transient slack: the slack that must be provided to cater for a change in speed of the ship, while the cable catenary adjusts to the new condition.

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Desktop Study of Site Selection for Submarine Optical Cable Engineering

In Submarine Optical Cable Engineering, 2018

4.1.2.2 Landing Site Visit

The desktop study for the submarine optical cable route shall include site visits to the proposed landing points of all route options. The site visit(s) shall examine:

1.

Distribution of villages and towns, land utilization, and coastal character near the landing point and other surrounding marine development activities;

2.

Beach topographic features, scouring and silting characteristics, and soil conditions at landing site;

3.

Climate and weather conditions and the potential impact on the cable landing operations;

4.

Existing infrastructure for landing and terminating a submarine cable, suitable locations to land the submarine cable and construct new suitable landing facilities (such as manholes, system grounding facilities and pipelines, etc.), if no existing infrastructure exists;

5.

Shore-end protection measures required (i.e., articulated pipe, directional drilling, etc.);

6.

Construction conditions of the cable landing, which may determine the cable landing type (such as landing directly using the main installation ship, or a small ship landing, or beach excavation, or directional drilled conduits landing);

7.

Conditions applicable to permits for previous cable systems installed at each landing point and assessed for their relevance to the proposed cable system;

8.

Interviewing the local government agencies and stakeholders concerned with the construction.

The primary landing points, as well as, where possible/practical, alternate landing points, should be marked during site visit.

A landing site visit report should be submitted after the site visit. The report should, at a minimum, include such data as:

1.

Landing site description, including photos, manhole and landing point location, land measurement results, and related charts;

2.

Site accessibility (roadway width, surface, etc.);

3.

Working space assessments;

4.

Beach evolution and potential for beach erosion during severe storms;

5.

Maritime development activities such as maritime transport, fish farming and fishing, and water conservancy;

6.

Beach utilization by the public and implications of applying access restrictions during laying operations;

7.

Communication conditions, such as radio permits, cell phone/mobile signal strengths;

8.

Local facilities such as civil contractor availability, shore end support, divers, hotels, etc.;

9.

Transport facilities, such as the airports, taxis, local ports, the convenience of truck hire, etc.;

10.

The list of interviewed organizations, units and personnel, the content of the interviews, and the opinions and suggestions of the respondents;

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Geophysical and Geotechnical Design

Jean M. Audibert , Jun Huang , in Handbook of Offshore Engineering, 2005

Lightweight Wheel-Drive CPT

The lightweight CPTs (figs. 16.49a and b ) are the most popular models for submarine cable route investigations, ploughing assessment and trenching studies. They typically consist of a 4-m-tall frame mounted on a 4-m-diameter seabed base-frame and weigh about 2.3 tonnes. The drive motors, wheel-drive and sensor systems are mounted on the base-frame.

Figure 16.49. (a) SEAROBIN CPT and schematic; (b) Starfish CPT

The wheel-drive operates the same as the large version but uses only two steel wheels and can apply only a thrust of up to 15 kN to the 10 cm² cone. The CPT cone rod can penetrate up to 2 m into the seabed. Electrical power for the motors is supplied via an armored umbilical cable that is also used to deploy and recover the device from the surface support vessel. Lightweight wheel-drive CPTs normally include an array of ancillary sensors and samplers and can be deployed in water depths down to 1500 m. Some battery-powered versions can be operated in over 2000 m water depth.

The lightweight wheel-drive systems can be operated from most vessels fitted with 5 tonne SWL cranes or A-frames and having sufficient reach. Adequate deck space is needed to accommodate the smaller 20 kVA generators, 1500 m winch and for storage/handling. The design is particularly robust to enable high productivity rates to be maintained.

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Technique Developments and Market Prospects of Submarine Optical Cable Engineering

In Submarine Optical Cable Engineering, 2018

10.2.1.1 High-Tech Application

Because of continuous success in marine survey and seabed exploration, a number of innovative methods are applied in the submarine cable route survey. It makes the information acquisition and treatment more efficient, survey technique requirements more standard, and the quality survey results are substantially upgraded.

1.

Underwater positioning

The application of Difference Global Positioning System (DGPS) greatly improves positioning accuracy for survey ships. Nowadays, dual band DGPS is used for the submarine cable route survey and hence the positioning accuracy is improved up to the decimeter. After being equipped with an underwater positioning system, the acquired data quality of towing underwater sensors is substantially increased.

2.

Digital geophysical survey technique with high resolution

Multibeam sounding and interference seabed side-scan sonar are successfully used in submarine cable route survey. This makes a fully covered and highly precise topography measurement possible. The application of digital sonar, synthetic aperture sonar, three-dimensional sonar, and specially used computer sonar working stations improves the resolutions of seafloors and submarine targets. With highly accurate positioning, the mosaic pictures recorded by high-quality sonar are widely used. The sub-bottom profiler has evolved from analog into digital. Specially used computer working stations, chirp tech, and parameter array technology increase the resolution in shallow-layer inspections. The assembled towing of a magnetometer and an underwater transducer with a side-scan sonar meets the expectation of a ferromagnetism target inspection.

With the facility of this submarine digital geophysical exploration with high resolution, the large-scaled and fully covered measurement of the submarine optical cable route corridor zone is achieved. It is capable of obtaining a variety of uninterrupted undersea information with high quality. Due to a series of advanced software (Caris Hips/Sips, Triton-Elice, etc.), the data is processed and displayed in real time with high efficiency. Recently, equipped with geophysical prospecting or sampling apparatus, cameras and other instruments, the deep tow, underwater remotely operating vehicle (ROV) and autonomous underwater vehicle (AUV), as the working platforms, are the efficient methods for near-sea bottom, short-distance, and close-target survey.

3.

Seabed in situ testing

A number of technique methods are available for seabed in situ testing in the submarine cable route survey. The most widely applied is cone penetration testing (CPT), and its development is the most outstanding testing method.

CPT used in the submarine cable route survey consists of a mini-sized cone-type penetrometer, a base frame with ballast installed in the seafloor, thruster, and data acquisition/process instruments. The mini-sized electric cone is used for the measurements ofcone-point resistance and cone-side friction resistance. In the past 10   years, the expectation for CPT research has been multifunctional, with real-time data processing and display. The latest product developed by FURGO International Group is MIP-HPT-CPT: Membrane interface probe (MIP)-Hydraulic profiling tool (HPT)-Cone penetration testing (CPT), with features such as multifunctional probe and a specially developed software package. It is capable of several measurements including penetration resistance, pore water pressure, and gradient. After data processing, a series of figures will be created, concerning the relation curves of a variety of measurements and derived parameters, against the penetration depth. They are used for the information of soil layer, soil conditions, relative density of granular soil, overconsolidation, and sensitivity of cohesive soil. In addition, MIP-HPT-CPT is capable of measuring the soil conductivity, dynamic pore pressure, and pollutants contents. The distribution diagram of pollutant contents in two-dimension and three-dimension are obtained after the data processing, as is the pollutant dispersion flux. The developed software package includes Programmable logic controller (PLC) software to process MIP data, UNIPLOT software to process CPT data, and GeoDin for visualization treatment. Another product developed by FUGRO International Group is seismic cone penetration testing, a multifunctional probe. It can measure the wave velocity of pressure wave (P) and shear wave (S) in order to calculate soil features such as Poisson's ratio, elasticity module, bulk module, and Young's modulus, etc. The development and application of a CPT multifunctional probe improves survey efficiency, reduces its cost, and provides more reliable scientific and technique grounds for submarine cable route site selection or route conditions evaluation.

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Cabling to connect offshore wind turbines to onshore facilities

Narakorn Srinil , in Offshore Wind Farms, 2016

13.3.1 Preinstallation survey

Detailed preinstallation survey and mapping of offshore geotechnical, environmental, archaeological and meteorological conditions are essential to the selection of subsea cable routes, corridors, layouts, installation planning and methodologies. They are also useful for the identification of potential hazards and obstacles which can impact on the cable laying and burial operations. These include, for example, large rocks, wrecks, unexploded ordnances, areas near an aquaculture farm, and existing pipeline and cable infrastructures, especially in the North Sea regions. In general, a 500-m Advisory Safety Zone (ASZ) is requested around all installation vessels, while in the wind farm construction area a 50-m ASZ around each installed turbine is required. A 250-m ASZ is required along the export cable route ( The Crown Estate, 2012).

For geotechnical explorations, the preinstallation frameworks may include the cone penetrometer, boreholes and vibrocore tests of soil samples at a maximum depth of 5   m below the mean seabed level, within a wind farm and along the potential export cable routes (Worzyk, 2009). Cable burial trials may also be conducted in advance to make sure that the desired burial equipment is appropriate for actual seabed conditions while achieving the burial depth requirements. Such trials should be planned and carried out through a certain length (eg, 1   km) covering different soil types.

From a geophysical standpoint, the location and mobility of sand waves along the cable route should be determined to assess whether such features could be avoided or, if impossible, whether seabed preparation or clearance is required to ensure the stable seabed character maintaining the burial depth index and without uncovering the buried cables in a short period of time.

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System planning and deployment

Loic Lefur , in Undersea Fiber Communication Systems (Second Edition), 2016

Landing station

Another point, which has proved to be one of the major risks in delays, consists of the terminal stations and land route (cable conduits and necessary manholes from the beach manhole to the station) readiness. Most of the time, the terminal station already exists, and only limited work is required, for instance refitting a transmission room or upgrading the power plant. However, when a new cable station needs to be implemented, purchasers run into a battle against time. A terminal station is a complex building. Indeed, just like for the rest of the system, it has to be designed in order to avoid any outage on the system. For instance, DC power (which feeds the transmission equipment and the power feed equipment) is fully redundant, and shall run seamlessly even in the case of a long outage of commercial power. Air conditioning equipment is also redundant, to avoid automatic shutdown of the equipment which is rather sensitive to overheating.

Building a new submarine terminal station is thus complex due to the number of subcontractors required and the coordination required between them. Therefore, the 6 to 12 months window (the station needs to be ready roughly 6 months before the expected provisional acceptance for equipment installation) allowed for building and equipping the station together with its associated land route becomes rather short, especially if building permits are required and land needs to be purchased!

Recently, containerized stations have been proposed on some systems to mitigate the risk of delay due to station unavailability. They consist of pre-equipped containers with all necessary service equipment which are shipped and assembled on site (like Legos). Such a solution allows limiting the landing party responsibility to only providing the necessary land, concrete slab and the connections to basic utilities.

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Submarine Cable Project Management and Maintenance Monitoring Information System

In Submarine Optical Cable Engineering, 2018

9.3.5.5 Automatic Alarm Function

According to the Provisions of the State Council on the Protection of Communication Lines, the two nautical miles of water area on each side of the submarine cable route shall be a submarine cable protection zone, in which shall be prohibited anchoring, trawling, or other operations endangering the safety of submarine optical cables. Once the ship enters the preset protection area of the submarine cable and the speed is lower than the set threshold, the color of the ship turns into a striking red, accompanied by a sound and light warning, reminding the monitoring personnel to deal with it.

Details of the ship will also be displayed in the list of ships on the interface. When the speed of the offending vessel is higher than the threshold value or leaves the protection area, the alarm will automatically stop, and the ship is automatically removed from the list of ships.

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