Calculate power distribution unit load and remaining capacity across connected circuits.
PDU utilization compares connected equipment load against the unit's rated capacity, but continuous loads — like always-on server equipment — should be kept at or below 80% of that rating, the standard electrical derating margin that leaves headroom for inrush current and avoids nuisance breaker trips. Utilization above 80% is a warning sign even if the PDU hasn't tripped yet; above 100% risks an overload trip.
PDU utilization
utilization% = connected_watts / pdu_capacity_watts × 100
Continuous electrical loads are conventionally derated to 80% of a circuit or PDU's rating (an NEC-style convention) to leave margin for inrush current at power-on, temperature effects on conductors, and to avoid nuisance breaker trips under sustained load — the PDU's 100% rating is a hard ceiling, not a comfortable operating point.
Nameplate (rated) power is a conservative upper bound and useful for initial planning, but measured/metered draw reflects real utilization more accurately, since equipment rarely runs at full nameplate power continuously. Use metered PDU data when available for capacity planning decisions.
Redistribute equipment across additional PDUs or circuits, migrate to more power-efficient hardware, or verify actual draw with a metered PDU rather than relying on conservative nameplate ratings that may overstate real load.