As we have discussed before, 1500va is 1500 volt-amps.
Volt amps are an absolute real technical value... however in the UPS world volt amps is a nominal or descriptive term.
As an example... APC's 1500va unit is actually a 1440va unit and APC's 2200va is a 1920va unit
Why the mis-naming?
2 Reasons:
Volt amps are an absolute real technical value... however in the UPS world volt amps is a nominal or descriptive term.
As an example... APC's 1500va unit is actually a 1440va unit and APC's 2200va is a 1920va unit
Why the mis-naming?
2 Reasons:
- Marketing - bigger numbers sound better
- Technical - with modifications you can achieve the full VA rating.
I'll pass on the Marketing reason for now and focus on the technical
Look at the following picture from the back of an APC SUA2200. It shows the Max Output for 2200 and 3000 va UPS based on the Input Plug
As you can see, if you buy a SUA2200 with its standard 520P 20A plug, it will only provide 1920va worth of power. If you put a 30amp plug on the unit, it will give you the full 2200va rating. If you put a 15amp plug, you get a 1440va unit.
All of this is because a 20amp electrical circuit cant really give you 20amps. National electrical codes and guidelines suggest a maximum 80% rating for a circuit. That means your 1500 (15a) is a 1440va and your 3000 (30a) is only a 2880va.
So thats one of the reasons why you will see our 2200va units including the SUA2200 (200b) get a L530P plug. Its not that we are smarter than APC, but just a bit more honest.
