Plug and Play Transformers and 110V Distribution for Shipyards

Overview

Although 110V plug-in power and lighting systems were originally developed for the construction sector, 110V Reduced Low Voltage has been embraced by many other sectors, including shipbuilding, where there is a similar need for safe, easy to use, temporary power and lighting. On a recent project, there was a requirement to update equipment at an existing yard where 110V systems had been in use for a considerable period. However, there was a particular wish to address a variety of concerns relating to the transformers and also an opportunity to improve the 110V distribution equipment.

The transformers had previously been oil filled and were not easy to move around the yard or on the vessel. The solution was to move to an air cooled transformer mounted within a heavy duty, protective crash frame with fork lift pockets and overhead lifting facility. Because the transformer is typically installed in an external location, the enclosure needed to be non-vented and provide ingress protection to IP55. The decision was also made to fabricate the enclosure from grade 316L stainless steel, as the intention is for the transformers to be in service for 10 to 20 years despite the harsh installation conditions. The supply to the transformer is via a plug-in 125A 400V appliance inlet and the load connections are via 4 x 125A 4P 110V sockets, each with MCB and variable RCD protection.

The 110V distribution assemblies are based on our B3+ enclosure, which also provides ingress protection to IP55. The assembly is fitted with a 125A, 3P+E 110V appliance inlet and also a loop through 125A 110V socket. The assembly is fitted with 9 x 32A 3P 110V sockets for power and 9 x 16A 110V sockets for temporary lighting. All sockets provide 110V single-phase but the 16A sockets are 4 pin, which eliminates the risk of lighting being unplugged so that powertools with standard 16A 3 pin plugs can be supplied. Each socket is provided with DP MCB and 110V RCCB protection.