EP500 UPS (never interrupted) with solar and A/C inputs

I am using one EP500 as a UPS for a refrigerator, plus home network equipment. I don’t want the output to ever switch off unless there is no PV or A/C inputs and the battery is dead. What mode will let me charge with PV, run on battery overnight, but will switch to A/C input if the batteries get to the low SOC number? I know this sound simple, but the manual certainly does not make this clear.

● Note: In PV Priority Mode EP500 can only be recharged via grid to 20
% capacity, and discharge to 20% of the capacity (you can tweak it to
100% for full grid charging manually on screen or App) as the Reserved
capacity setting in PV priority Mode. And rest of the capacity will be
fully charged by solar power and 2nd adaptor only

@newcx The setting you are looking for is PV Priority UPS which is under settings and the second screen 3rd. menu item down “Working Mode”. You can select PV Priority UPS and set the threshold to 20% if that is what you desire.
I hope this helps.

Thanks. The documentation and the app do not make it clear that A/C kicks in when needed. The device screen has text that describes it better and it seems to be working as expected.

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Update: Last Wednesday morning my EP500 shut off the output again while in PV Priority mode. The output was off for about 20 minutes, but when I noticed it was off the input A/C was on and charging. I had the Reserved Capacity set to 15%, but the battery showed 9%. I turned the output back on and it kept charging from A/C then recharged from PV when the sun hit the panels. It is always connected to a reliable A/C input and can draw from that when it wants. Since Wednesday it has been cloudy and the battery level has dropped to 14% with no more output interruptions.

Once again: Found my EP500 output off again this morning. Yesterday was cloudy so I changed modes to Time Control to give the batteries about 3 hours to charge from A/C. My bad for changing modes, I guess. I left it in that mode overnight and woke up to find the output A/C off and battery at 3%. Changed to UPS mode and it was in Standby mode (don’t know if this has any effect when in other modes), so I changed it to Online. Had to wait for the batteries to get to 5% before the A/C output would come on. I have a pair of EP500s not connected together so I may swap units to see if the other one has problems keeping the output going.

Again, a UPS that chooses to turn off the output when the A/C Input is available is not a useful UPS. Can Bluetti address this?

I’m officially done with Bluetti for UPS and regret my purchases. I supported the EP500 on Kickstarter, but as a UPS they have completely failed. My EP500 turned off the output again last night. I checked it around midnight and it had 37%. I knew it would get low overnight, so I left it in PV Priority mode hoping it would start charging at 20%. I found it in the morning with the output off and battery level at 20%.

My EB3A has always been iffy, but now I know that it drops the output for less than a second whenever it wants. I had two Aerogardens connected to the A/C output, one old and one of the latest generation. The old one was blinking the grow light many times a day, but the timer did not reset, so I didn’t assume it was the EB3A. I added a new digital Aerogarden and it wasn’t working right. It turns out that the power drops coming from the EB3A cause the new unit to complain that the power went out, and it stops working until I tell it to continue. I moved the plug to a wall outlet and everything is working fine.

Bluetti needs to stop marketing and selling UPSs until it can fix the issue that A/C output is not a priority. When there is either battery power, wall power, or both the A/C output should never be interrupted!

Hi, I read through your posts and curious if you are still using the EP500. I’m considering it for Time of Use, but it looks like from your experience it hasn’t worked out like how it’s supposed to?

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Hi Spyris. Yes, I am still using two EP500s as battery backups for a refrigerator, a freezer, and my home network. One EP500 has about 1800 watts of solar directly connected, the other is only grid powered. I have both units scheduled to recharge during the day from the grid. Because the EP500 is not a true UPS I just make sure that the recharge time is sufficient to keep the batteries above 20-30%. Doing this I have not had either unit cut the output power for many months.

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