UPS units have a power handling and battery module. In rackmount units, they combine these 2 modules into a various form factor or rackspace thickness, called U.
Most manufacturers make a 3000va unit in a 2U, 3U or 5U format.
While there is no difference* in a the power handling capacities of each form factor, there are big differences in the battery capacity.
A 3000va 2U UPS unit using 1500va like the SUA3000RM2U has a runtime of 10min. A 3000va 5U UPS unit using 1500va like the SU3000RMNET has a runtime of 19min.
This difference is because of the size of battery capacity.
Remember, while we express POWER capacity in VAs, we express BATTERY capacity in VAhs. And this battery capacity is limited by physical space of the form factor.
Notice the battery capacity of the various 3000 units.
- SUA3000RM2U - 480VAh (10min)
- SU3000RM3U - 672VAh (15min)
- SU3000RMNET - 864VAh (19min)
