The project aims to install a real time monitoring system utilising Distributed Acoustic Sensing (DAS) on several new subsea cables. The DAS system will utilise the single mode fibre optics embedded within the cable. A DAS interrogator unit connects to the optical fibre which essentially turns the fibre into an array of virtual microphones. Short pulses of highly coherent light are transmitted down the fibre by an interrogator unit, and backscatter returns are observed. The backscatter observations detect minute cable strains induced by acoustic events, which when passed through to a processing unit can provide interpretations and visualisation of the signal.
Real time monitoring of submarine cables will give SSEN a greater understanding of the conditions in which our cables operate and proactively manage mechanical wear and tear of the cable, thus preventing associated lost or interrupted supplies. This monitoring will notify us when there is an immediate concern to the health of the submarine cable or safety of nearby marine users. Submarine cables are one of the costliest assets within the Distribution network and currently command the highest Asset Health Points per unit in the Common Network Asset Indices Methodology (CNAIM). Being able to identify a fault location in real time will allow us to carry out repairs quickly and effectively, before they pose a potential risk to other marine users.
August 2018 – August 2021