Upgrading a UPS with a bigger battery?

Enderg60 · Dec 1, 2023

To start, my goal is to power 4 vectra L2s, and an Abyzz A400 for two minutes when the power goes out. I have a natural gas generator that kicks on after that. Im just trying to fill in the gap.

I purchased a 850 VA UPS in hopes that would work but it starts beeping and shuts off after only 10-15 seconds. I dont have room in the electrical box for a larger UPS but I could remote mount a larger battery elsewhere. Would this actually work, or am I limited by the inverter size in the UPS?

Thanks!

EricR · Dec 1, 2023

Without knowing anything about the equipment, 850 Watts sounds like a lot to me.
Does "850 VA" actually mean the UPS handles 850 Volt*Amps (Watts) output or is that just a confusing model number or something?
Does it have a max Watts rating for AC output?

Enderg60 · Dec 1, 2023

Its this guy here.

https://www.apc.com/us/en/product/B...-2-usb-charging-ports-9-nema-outlets-3-surge/

It apparently only provides 450w.

slythy · Dec 1, 2023

My build thread

Here is a link to my post in my build thread of what I did. I used a high end UPS model and added fans on the electronics so It could handle extra heat of running longer. I only run my return and 2 MP40's off of it.

You have to be careful with cheapo UPS's as the electronics were never designed to run for long extended periods of time.

Enderg60 · Dec 3, 2023

Do you think something like this would work with a marine battery?

Invert with ats

I figure I'll still need a trickle charger but that's easy enough to find

dschuffert · Dec 3, 2023

I am in a similar situation. About two minutes from when my commercial power drops, the generator starts and warms up, then switches from the commercial power to the generated power. I ended up going with this unit to bridge the gap.

I had a smaller unit at first that didn't work well for me. If I exceed its capacity, the APC UPS unit will shut off (as smartly designed). I had to calculate my load and ended up with the APC 1500 model.

EricR · Dec 3, 2023

The devices you mentioned are all DC, correct?
If you can avoid DC-to-AC inversion and run them directly from DC battery, that would be more efficient but I don't have any experience with these pumps.

Internet search for Vectra L2 shows "150W power supply" so I'm just guessing that's your problem with your current UPS -- 4 of those are probably too much for your UPS inverter.

Enderg60 · Dec 3, 2023

I have other devices that are not DC and it's simply easier to keep the 120v system active.

My abyzz for example does not run on 12v

Aquavaj · Dec 3, 2023

Basically the runtime is dictated by the battery size and power output by the inverter electronics. It's shutting off likely due to exceeding the output. A 1500VA model should kick you up to around 900w with a runtime of a little over 2 mins at max output.
I have not done this but I don't see why you can't hook a car or marine battery to it to extend the runtime. You may have to beef up the connecting cables and run an external trickle charge to keep it topped off though.