In the design of tomorrow’s port terminals that are destined to handle intermodal container cargo, it is important to consider the needs and impacts of the refrigerated containers (aka Reefers) that will pass through the terminal.
The challenge for planners and developers of new terminals with regards to Reefers continues to be in anticipating the volumes and utilization of limited backland areas. Once the planning has progressed to the point of knowing how many Reefers versus Dry Containers will be in the terminal at a given time, the critical work regarding yard layout can begin. At this point, the number of Reefer spots, the space available, the means of moving, and the landside method of transit all need to be considered.
While the Reefer Outlets might seem to be an insignificant piece of the overall Port Terminal design, these Outlets will play a crucial role in long-term efficiency, safety, maintenance and cost of terminal operations. Key considerations when specifying reefer outlets in port terminals are as follows:
Materials and Configurations
Reefer Outlets are available in a variety of materials and configurations. The most common female receptacle is the 32A 480VAC type that complies with IEC 60309-1 and 60309-2. The receptacles are often plastic of various types, some more durable than others, while the most durable Outlets are stainless steel.
It is extremely important that the receptacle be safety-interlocked to ensure that it cannot be energized unless the correct mating plug is properly inserted and mated – this is to protect the operator from making or breaking the electrical connection under load. While the safety-interlock is not typically required by code, it is a global industry standard and good common sense. The Reefer Outlet should also provide overload and short circuit protection to coordinate with the site’s power distribution system.
Rack-mounted Reefer Outlets
In rack systems, the positioning of Reefer Outlets is critical to ensure adequate access to plug in the Reefers, minimize the distance the operator must pull the power cord, reduce the amount of conduit/wiring to the Reefer Outlets, and not block the walkways.
Ground-mounted Reefer Outlets
Reefer Outlets can also be mounted in low concrete bunkers, 2 to 4 outlets per bunker, or on upright pedestals which provide easier access to the receptacles but are also more susceptible to damage by trucks and other yard vehicles. Pedestal designs often incorporate protective bollard systems; these are expensive but provide a much safer and more resilient system.
Reefer Outlet Enclosure Housing
In specifying the enclosure housing for the Reefer Outlets, the orientation of the enclosure, the mounting method, the receptacle orientation, location/size/protection of the incoming conduits and upstream switchgear, and the environment all must be weighed in choosing the proper Reefer Outlet configuration. In marine environments such as port terminals, the typical enclosure is stainless steel.
Reefer Outlets can be outfitted with options such as indicating lights, plug sensing, breaker trip alarm, power factor correction, and rear-actuation which insures the operator is not in front of the plug when the outlet is energized. The long term benefits of each of these options needs to be weighed against the initial installed product cost.
The designer/engineer must keep in mind the most important aspect of the Reefer Outlet system; all of the Outlets need to be safe and operational all of the time to ensure that no cargo is spoiled or lost due to the absence of power to the Reefer. The cargo value of a single Reefer can be worth more than the installed cost of a hundred Reefer Outlets, and yet the terminal operator will expect that outlet to provide power to thousands of Reefers over its lifetime.
Click here to read the full article, “Specifying Reefer Outlets for Container Port Terminals” previously published by World Port Development.