When dealing with power architecture on high-end arrays like the FlashArray//X90 R4, understanding the difference between the base chassis and the expansion shelves is critical. The base //X90 chassis-housing the powerful Intel CPUs, massive memory footprint, and primary PCIe lanes-draws significant wattage and strictly requires 200V-240V (208V minimum) power inputs to function. It will literally not power on if plugged into a 120V circuit.
However, a DirectFlash Shelf (DFS) is merely an external NVMe-oF expansion enclosure. It houses the DirectFlash Modules (DFMs) and the necessary backend I/O modules, but completely lacks the compute- heavy controllers of the main array. Because its overall power draw is significantly lower, the official Pure Storage hardware specifications state that DirectFlash Shelves are fully rated and completely supported to run on standard 120 VAC power indefinitely.
Therefore, the Implementation Engineer can confidently cable the DFS power supplies into the available
120V PDU connections without sacrificing any performance, redundancy, or hardware lifespan. It is a fully supported, permanent configuration.