How to calculate UPS Size?
When calculating the size of a UPS, it is important to take into account the following: Apparent power (VA or kVA) – This is defined as S=VxI for single-phase loads, S=(VLI x ILI)+(VL2xIL2)+(VL3xIL3) for three-phase loads where V is the voltage, and I is the current absorbed by the load under normal operating conditions (EN50091- 1-1). This information can usually be found on rating hardware labels, and in the documents and information supplied with the system(s) to be protected. It is generally over estimated. Active power (W or kW) – Is defined as P=Sxpf where pf is the power factor. If the value of P and pf of the load(s) are not specified, the power absorbed must be precisely measured in order to correctly size the right UPS. The typical load of a computer is associated with a pf of between 0.65 and 0.8. Active power is particularly relevant when sizing batteries. Overloads – Are voltage and current demands on the UPS in excess of its specification. They may be temporary during ini
When calculating the size of a UPS, it is important to take into account the following: Apparent power (VA or kVA) This information can usually be found on rating hardware labels, and in the documents and information supplied with the item. It is generally over estimated. What is UPS in Parallel And Redundant Configuration? In network, enterprise wide and industrial installations, UPS may be connected in parallel or redundant configurations: Parallel – To obtain a kVA/kW output higher than that of any single UPS. For example 2 x 200kVA modules may be connected in parallel to achieve a 400kVA output.
