Power and racks, sized properly
This is the category that only counts on the day the power fails, and then it counts completely. The question is not which UPS is largest but how many minutes are needed to shut everything down cleanly, or to keep running until the generator starts.
Four parts of a server room
They are ordered separately and should be sized against each other.
- UPS systemsFrom a box under a desk to a system for a whole room. What counts is the power and the time: the same UPS gives twenty minutes at half load and five at full.
- In-rack power distributionThe strip everything plugs into. A metered version shows consumption per outlet, and that is how you find out whether there is capacity left or not.
- Racks and cabinetsNineteen inch, with the depth and doors that suit the equipment. A wall cabinet in a back office and a rack in a server room are two different decisions.
- Cooling and monitoringSensors for temperature and humidity, and the cooling itself. Heat is why equipment fails sooner than expected, and it can be measured before it gets that far.
How we establish the capacity
Three steps. Skipping the first is why a UPS does not make it through a real outage.
Measure what is actually drawn
Not adding up what the labels say, but measuring what passes through over a week. The gap between those two is often a factor of two.
Establish how long it has to keep going
Enough to shut down cleanly is a different UPS from enough to keep working. Know which of the two it is before choosing, because there is no in-between.
Put the batteries in the budget
Batteries last three to five years and are a recurring line, not a one-off. A UPS with worn batteries gives no error and delivers zero minutes.
What belongs with this
Power is the underside of continuity.
Know how many minutes you have
Tell us what is in the cabinet. We measure consumption and work out how long it keeps running, including when the batteries are due for replacement.
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