The Power Module available for MakaiPlan Pro and MakaiLay includes a collection of tools that were developed for addressing specific issues faced by submarine power cables during installation. Power cables are heavier and more rigid than fiber optic cables. Their longevity can be severely compromised if they are not installed with the correct tension on the seabed. Thus, a successful power cable installation requires more careful planning and monitoring.
MakaiLay Power: Subsea Power Cable Control Software
Fiber Optic Cables versus Power Cables
Power cables are considerably heavier and more stiff than fiber optic cables. While fiber optic cables are installed with slack on the seabed, power cables have to be installed with some residual tension to avoid a bend radius smaller than the Minimum Bend Radius (MBR) recommended by the manufacturer, which could kink and damage the cable at the touchdown (as seen in Figure 1 below).
Due to the fact that conventional installers of power cables do not have the means to accurately estimate the cable tension on the seabed, they operate with very high safety factors. Consequently, power cables are usually installed with tensions that are much higher than the required values. Cable suspensions occur more often than desired as a result. As shown in Figure 2, at these seafloor contact points, large reaction forces and small bend radii are common, thereby reducing the life expectancy of the cable due to increased wearing and chafing.
Figure 1 (left): Too little bottom tension or bottom slack will cause excessive bending of the cable.
Figure 2 (right): Too much bottom tension will create spans on the bottom creating heavily loaded contact points.
To maximize the life expectancy of the cable, the power cable installer must accurately lay the cable with low values of bottom tension to avoid cable suspensions, but at the same time maintain a small amount of tension at the touchdown to maintain bend radii above the MBR. The bottom tension and cable touchdown location can be accurately managed using MakaiPlan Pro and MakaiLay with the Power Module, both of which have the capability to accurately model the 3D cable shape, touchdown location, and tension on the seabed during a lay.
Interested in Makai’s Submarine Cable Software and Services?
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