Bakker Sliedrecht to retrofit propulsion drives of multi-functional vessel

The Granuaile is a versatile class 1 DP vessel that is used to place and service 150 offshore buoys, as well as supporting the management and maintenance program of a further series of lighhouses and beacons around the coast of Ireland and Northern Ireland. The vessel has a 20t crane, towing and tugger winches, a large aft deck, a modern spacious bridge and a helipad. It is also used, among other things, for measurements at sea, inspection, sampling and mapping of shipwrecks and seabeds, cable and pipeline route survey, salvage and helicopter operations.

Solving dimensional differences between ACS600 and ACS880

The vessel has diesel-electric propulsion, powered by two 1100 kW electro motors. The Granuaile also has a 1200 kW electromotor for the bow thruster. Electrical system integrator Bakker Sliedrecht originally supplied and installed the drive modules for the multi-functional vessel Granuaile, and has carried out regular maintenance during her active service life.

Since the early 2000s, the three ACS600 frequency drives that drive the electric motors have become obsolete. As the modules are no longer supported by the supplier, Bakker Sliedrecht is replacing them with new ACS880 modules.

However, the panels in which the new modules are to be installed turned out to be difficult to reach. Bakker Sliedrecht will solve this problem by building new frequency inverter modules in the panels of the brake chopper. This way, they are easily accessible. The modules for the brake chopper are moved to the panels of the old frequency drives.

The retrofit project is also noteworthy as it concerns the retrofit of air-cooled rather than water-cooled modules.

A boom in retrofits

Bakker Sliedrecht equipped many vessels with ASC600 drives around the turn of the century. Many of those modules now need to be replaced to keep the vessel in service. For example, Bakker Sliedrecht recently replaced all the frequency drives of several naval vessels.

Account Manager John Hollemans and Project Manager Fred Hordijk of Bakker Sliedrecht: “Since our installed base with ASC600 drives is large and these have become obsolete, we expect to see more similar retrofits in the near future. To serve our customers the best way possible, we have developed a standard “box in box” technical solution. This way, the refit can be done fast and efficiently. Bakker Sliedrecht can also help other customers with an existing ACS600 installation using the standard box in box solution.”