Power equipment
The equipment in a data-centre power chain
What each part does, what to check before specifying one, and what its maintenance actually involves. Every guide names its sources and the date it was last reviewed.
UPS systems
- UPS systems: what they do and what to check before specifying oneAn uninterruptible power supply carries the critical load through the seconds between a utility failure and the generator taking over. What it protects against depends entirely on its topology, and what it can carry depends on figures that are easy to read off a nameplate incorrectly.
Batteries
- UPS batteries: the consumable in the power chainThe battery is the part of a UPS with a service life measured in years rather than decades, and replacing it is the expected maintenance event rather than a failure. Most of what goes wrong is decided by room temperature, by what was ordered, and by whether anyone measured the string before it was needed.
Power distribution
- Rack PDUs: distributing power inside the cabinetA rack power distribution unit is the last piece of the power chain before the equipment, and the one most often chosen on price. What it costs to get wrong is stranded capacity, a tripped breaker during a failover, or no idea which cabinet is drawing what.