9 ms·
Standby UPS topologies like the APC Back-UPS lines keep the battery out of the loop until a loss of power from the AC input is detected, at which point the inve
by snuxoll 6y ago
Standby UPS topologies like the APC Back-UPS lines keep the battery out of the loop until a loss of power from the AC input is detected, at which point the inverter kicks on the the transfer switch takes the feed from there.
This is a design choice from APC, money is on the control electronics being powered off the battery meaning a dead or missing battery means the entire unit is non-functional. Making the unit resilient to this probably costs as much as a line-interactive unit, however, so you might as well just tell people to get a better unit than make a middle-ground solution.
- formerly_proven 6y agoI have a line-interactive APC and it most definitely is just a UPS-shaped brick without a battery. Might have changed in newer models, I wouldn't know.
- zaarn 6y agoMy APC BackUPS Pro (supposedly line interactive) runs fine without battery (ran it with a tab from shipping still in the case), might depend on the setup. Generally line interactive makes little sense why it wouldn't work without battery since the power rail is shared.