UPS or Inverter + Batteries?

Jack Marlow

Honorary Master
Jul 18, 2008
I want to run computer equipment - around 2000 W with another 2000 on the way in a few months. What would you suggest for the backup power? My priorities in order of most important to least important are:

1) Surge protection
2) Buffer from brownouts and general fluctuations
3) Ability to run while power is down (1-3 hours)
4) Ability to connect solar at a later point.

For 1) should I just get surge protection at the DB? I also need it at the Cat5 cable since it routes outside / underground.
Would it be better to get an Inverter + MPPT charge controller + Batteries for now (charge controller connected to Eskom) or should I consider a UPS? Which is more efficient? Is the charge controller a waste without the panels? Cost wise I imagine the charge controller + inverter + batteries rivals a good pure sinewave online UPS.

I'm thinking 6kva min.


Well-Known Member
Feb 15, 2016
Pm of you're interested in a UPS. I've got 2 Eaton UPS' that's lying around, model 9PX5Ki. 5kva units with decent batteries as well as extra battery packs.