6.4 How containers connect to PCS skids, transformers, and the grid

The connection sequence

Once a container is set and anchored, the next phase of work is electrical connection. DC cables run from the container’s DC connection points — typically located at one end of the container — through underground conduit to the PCS skid. The PCS converts that DC to AC. AC cables then run from the PCS to a medium-voltage transformer that steps the voltage up for transmission to the project’s point of interconnection with the utility grid.

Communications cables — fiber or copper depending on the project design — run from each container to the site network infrastructure that connects the container-level BMS to the site EMS and SCADA system. These communications runs are installed during the underground electrical phase and must be pulled and terminated before commissioning begins.

The grounding connection is made between the container steel and the site grounding grid during the grounding installation phase. Every container, every PCS skid, every transformer, every piece of metallic equipment on the site connects to a common buried copper grounding grid that provides the fault current path required for safety. The grounding system module covers the design, installation, testing, and documentation requirements in detail. What matters here is the conceptual picture: the container is the building block, DC cable connects it to the PCS, AC cable connects the PCS to the transformer, and the grounding grid ties everything together underground.