OOI Science Plan: Exciting Opportunities using OOI Data
in testing speed and accuracy. In 2016, the program shifted from manual testing to an automated cable test system for all copper wire cables, thereby reducing the time and number of employees needed. The MIOs have engaged with vendors to improve quality control and are capturing data to calculate component life cycle, predict failure, and improve platform reliability. All cables are now serialized and tracked to identify trends and determine appropriate replacement cycles (e.g., neoprene cables do not appear to hold up as well as polyurethane). Furthermore, a visual inspection has been implemented along with cable protection and handling best practices. To improve asset tracking, a spreadsheet of serial numbers and pass/ fail test results is kept. Cables are tested as soon as possible after recovery, because faults can disappear when cables are tested dry. Over time appropriate replacement intervals will be determined for different types of cables. For example, it was discovered that the majority of failed cables used one specific connector. By working closely with the vendor, a leak path was discovered, generated by cathodic delamination between the metal connector shell and the polyurethane material that molds it to the polyurethane cable. After the vendor modified
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the connector design and molding process, < 5% of the cables failed the manual 50 V insulation test. In addition, stretch hoses need regular inspections as they do not appear to be returning to their original length. Stretch hoses may become entangled with fishing gear or damaged by fish bites, resulting in reduced or failed data transmission. By engaging with vendors, these technological enhancements and best practices are made more broadly available to the global observing community.
C. Biofouling Mitigation Biofouling has been a significant issue in coastal regions, but even off shelf, the Cabled Profiling Mooring’s 200 m platform has experienced significant biofouling (Fig. 5.1). Shutters and wipers have helped to keep most optical instrument surfaces clean. However, instrument modifications, including orientation, shading, and shutters, have not always been effective. Data quality was improved on the AC-S Spectral Absorption and Attenuation Sensor by using copper plumbing. The most successful mitigation on instruments is using a UV light antifouling system on sensitive instruments and cameras. Biofouling on the Coastal Surface-Piercing Profiling Moorings also
FIGURE 5.1 OOI’s Cabled Profiling Mooring experienced significant biofouling. Credit: NSF-OOI/University of Washington.
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