Many high end UPSes offer Bypass switches on their systems. These systems allow power to flow past the UPS, directly to the load. The purpose is to allow the UPS to be serviced without interrupting the load. Unfortunately, this feature is very expensive for some reason.
On smaller UPS systems, APC recommends a
SBP3000, which retails for $300.
On larger 5-16kva units, APC recommends a
SBP16KP, which retails for $900
Finally, get a large Symmetra 80kva unit and your bypass panel is a 42u cabinet called a
PD60F6FK1. This monstrosity retails for $14,000.
Essentially these bypasses are transfer switches. And like many electrical things in the UPS world, they cost almost 10 times more than they should. The SBP3000 can be replaced with a 2pole 30amp switch ($40), a small 60amp transfer switch ($200) replaces the 16KP thing, and a 200amp transfer switch ($900) can be wired to have the same effect as the PD60 thing.
So if you need a bypass, consider the APC units, but email if you want more info on these alternatives.
