The rating on the box assumes a load you probably do not have. Here is how to measure what your rack actually draws, and why the answer matters more than the brand.
A UPS is sold on two numbers: VA and runtime. Both are quoted against an idealised load, and neither survives contact with a real communications rack.
Start by measuring rather than adding up nameplate ratings. Nameplate figures are maximums — a switch rated at 150W may draw 40W in normal operation, but the PoE cameras hanging off it will not. A clamp meter on the rack's supply for a working week costs nothing and gives you the real profile, including the afternoon peak when everyone is on a call.
Then decide what runtime is actually for. There are two honest answers and they lead to different equipment. If runtime exists to ride out short outages and keep people working, you are sizing for hours and you want an inverter with a proper battery bank. If it exists only to shut everything down cleanly, you need ten minutes and a network card that can signal the servers to power off.
That second case is the one people skip, and it is the one that corrupts databases. A UPS with no shutdown integration does not protect your data — it just delays the crash until the batteries are flat, which is usually the worst possible moment.
Finally, test under load. Pull the mains at a quiet hour and watch what happens. Batteries degrade, and a unit that carried the rack for forty minutes when it was installed may carry it for six after three years. If you have never tested it, you do not know which one you have.