JB Switchgear Solutions (Pty) Limited recently completed a contract for electrical switchgear assemblies on a marine vessel.  The clients’ requirement was for a reliable high current application to enable powering up of the entire ship with full remote control of the electrical switchgear.

The first phase was to design a main DB to accommodate incoming power from four main generators, and to distribute said power throughout the ship.  The design of the 6000A U-shape assembly allowed fitment into a switch room with restricted space.  Control is achieved via synchronising check relays, ensuring safety, and preventing multiple breakers from closing onto the common bus.

The second phase included the main and emergency power board designs installed into dedicated switch rooms which supply and control normal and critical systems throughout the ship.  In this case also, space was very restricted and necessitated a modular design to reduce the length of the assembly, using withdrawable inserts for the feeders and motor starters.  Up to 20 starters were fitted into a single tier to achieve a compact yet accessible result.

In the interest of safety halogen free cables were used for all wiring to reduce the risk of sparking within any of the functional units.  The withdrawable inserts allow for minimum downtime in the event of a fault, since a spare can immediately be inserted in its allocated space whilst the faulty unit is repaired.