Planning a server rack requires balancing power capacity, cooling airflow, and physical weight limits. Here are the key numbers.
Rack Capacity Planning
| Factor | Standard 42U Rack |
|---|---|
| Usable Space | ~36U (leaving space for PDU, cable mgmt) |
| Max Weight | 1000-1500 kg (depends on rack model) |
| Power (single phase) | 5-8 kW per circuit |
| Power (three phase) | 15-20 kW per rack |
| Cooling | Match kW of heat output (1 kW power = ~1 kW heat) |
Airflow
Hot aisle / cold aisle arrangement. All servers face the same direction. Cold air intake from front, hot exhaust out back.