Higher Capacity UPS for Longer Runtimes
To determine the size of the UPS that you need, identify the total power load (measure in VA/Watts) of the connected equipment, along with the amount of runtime required (in minutes). Also, think about any equipment that might be connected to the UPS in the future, which could affect the calculations for load and runtime.
Estimating expected UPS runtimes can be challenging, particularly when the consistency of the utility power is not well known. Selecting a UPS with a load capacity 30-35% above the required power load offers the advantage of longer runtimes. This can lower the risk of overloading the UPS and causing an unnecessary UPS shutdown.
Although the initial outlay of a UPS increases with its size because of the higher capacity required for components, long-term operating costs typically decrease. When a UPS operates below maximum capacity, it reduces the stress on components. Sizing a UPS to run loads significantly lower than its capacity also increases spare capacity for future growth, along with extending runtimes.