A short between the conductors in the .68 cable, located 2,850 meters (9,350 feet) up the cable, caused a power loss to the vehicles yesterday. The damage could not be repaired so the remotely operated vehicle team used the day to plan and spool the cable off the storage drum, manually lay roughly 2,900 meters (9,514 feet) of cable onto the deck and cut out the damaged section. The remaining cable was found to be in acceptable condition and will be re-terminated to continue operations. Image courtesy of the NOAA Office of Ocean Exploration and Research, 2017 Laulima O Ka Moana. Download larger version (jpg, 7.0 MB).
Image showing the first cut of the .68 cable, at 2,700 meters (8,858 feet). The three layers of steel are peeled back to expose the black core containing three electrical conductors (brown and green twisted), three fibers (black, red, and white with yellow end), and drain wire (curled white). The Fiber Response Team performed a quick termination on one fiber and confirmed that the short was an additional 150 meters (492 feet) up the cable. Image courtesy of the NOAA Office of Ocean Exploration and Research, 2017 Laulima O Ka Moana. Download larger version (jpg, 10.3 MB).

Cable Repairs and Seamount Mapping

July 19, 2017

Remotely operated vehicle (ROV) operations were cancelled today while the Global Foundation for Ocean Exploration engineering team initiated a herculean effort to repair the .68 cable. After power was lost to the vehicles yesterday, our ROV team spent the evening investigating the cause and found a short between the conductors, located 2,850 meters (9,350 feet) up the cable from the end terminated to the ROV. The short was likely caused by age and natural degradation, and unfortunately the damage can’t be repaired. The solution is to remove the length of cable up to and including the damaged section. Today, the ROV team used the entire day to plan and spool the cable off the storage drum, manually lay roughly 2,900 meters (9,514 feet) of cable onto the deck, and cut out the damaged section. By the end of the day, they were able to access the damaged section and test the remaining cable on the storage drum. The conductors and fibers were tested and found to be in acceptable condition for re-terminating and continuing operations. Tomorrow the team will re-terminate the wire to Seirios, conduct testing and be ready to dive the next day.

Meanwhile, the mapping team used the lemons (extra time they were given) to make lemonade. The added mapping time was used to further map the unnamed seamount to the west of “Keli” Ridge and to complete tests to improve the backscatter results of multibeam sonar.