Row head cabinet Pdb single line diagram distributes 400V 3-phase 50Hz utility power through a 630A main breaker with electronic trip and smart metering to dual PDB-A/PDB-B busbars. Four 63A three-phase circuits feed high-density compute cabinets 1-4 via individual metering, while five 32A single-phase circuits supply network cabinets and monitoring terminals with dual 63A hot-standby branches reserved for future expansion. Surge protection at main and branch levels protects against transient overvoltages across the entire row. This architecture demonstrates proper load distribution, circuit segregation, and redundancy planning for modular data center power delivery. Fork and customize this diagram on Diagrams.so to adapt branch counts, breaker ratings, or metering requirements for your facility design.