I have an AC180 that I am trying to at least temporarily use it in a way similar to a computer UPS for an always on server that draws around 150 to 175W total. My APC unit failed a few days back and I swapped in the AC180 for this. Anyways I see it’s constantly charging at around 300W with a 175W AC only load and the charging is making negative progress meaning it slowly discharges over days. If I turn off the server removing all but 39W of the load it will switch to charging at around 1KW and this will cause it to charge fully. It’s set to normal mode charging and I have no PV or battery input.
Edit: Interestingly the second the one server shuts down the charging starts at a reasonable rate and > 1KW. I have 2 PCs connected to the AC180. The workstation is off unless I am using it. A few minutes ago I shut the server down with the workstation up and the charging instantly started even though I am currently using over 140W. I will have to do some more testing including starting the server while its charging. It was down to around 48% left and a few minutes later with the server off its over 59%. The server has an EVGA 1000W supply while the workstation has a Seasonic 850W or so.
Edit2: The second I pressed the power on the server the Grid power went from 1.3KW to 400W and the AC output went from 140W to ~290W. The battery was 63% at that point. Also I have tested ECO mode on and off. charging mode from normal or turbo. I have tested power lifting on and off. None of these settings seem to help.
I see maybe 3 possibilities, 1. Grid instability, 2. Interference from the equipment being powered, or, 3. A possible issue with the AC180.
To possibly eliminate 1 or 2 of these I would suggest connecting a different load in UPS mode, perhaps from a different supply, to see if the AC180 is doing the same thing.
I have an AC70 which is connected to my Fibre optic input to the home, the WiFi Router and the home security camera WiFi/recorder. It has been operating like this for over 6 weeks to date.
The load shows 27W Grid input and 27W AC70 output, which = 100% pass through. Battery at 100%. I don’t check it often, but have seen capacity briefly drop to 99% and a very brief charge from the grid of around 275W. This is the approx charge wattage of the AC70 when set to silent mode charging. As I’ve mentioned in other posts this is probably due to the internal smart charger briefly checking the battery’s SOC. I have other chargers that do the same including, but not limited to, Redarc and Victron.
The AC70 is set to Eco mode = Off, Grid Self-Adaption = Off and Silent charge rate.
As an aside, I have 2 fridges in my kitchen, one is a 520lt inverter fridge freezer (main household fridge). The other is an “El Cheapo” 90lt drinks fridge.
I’ve tried both of my AC70s and all 3 of my AC180s on both fridges. The 520lt works perfectly from all 5 power stations in both UPS mode and with grid power turned off. The 90lt starts, stops and stays stopped, on all 5 of the power stations, with or without grid power. It is the only device I possess, that won’t work. So, by process of elimination, you should be able to eliminate 2 of the 3 I noted. In my case it’s the 90lt fridge.
Forgot to mention, the 90lt fridge works perfectly from grid which, every time I check is running at around 241 to 243VAC. My Bluettis all seem to hover around 230 to 232VAC, load dependent, which is still within the range most appliance’s compliance plate. However, just because a compliance plate gives a voltage operating range, doesn’t mean they will. 
Thanks. I expect its #2 or #3 or a combination of both. I probably will do some more testing tomorrow. One easy test I can do is turn the server off and more highly load the workstation. A more difficult test would be to swap power supplies however its a bit of work since they have different modular cable sets.
I suspect it may be at least partially #3 because of when I first got the unit (late November 2023) it made a loud pop sound (like a spark) 2 to 4 times randomly over a period of months but hasn’t to my knowledge done that since. Each time that happened the load was just a high end laptop (230W power supply) and a monitor. I was sitting a few meters away from the unit so it was quite startling. It seemed to work fine with the laptop load and it didn’t appear to do this at all. I have also used it to power a refrigerator when we had a 25+ hour power outage. In that process I took it to a family member (who still had power) 2 times to be recharged so that we could keep the refrigerator going. It worked very well for that.
Did you turn on grid enhancement mode? What is the charging state of your AC180? Constantly charging at around 300W would indicate to me its in “silent” mode. I’ve heard of firmware problems related to the DSP when trying to enable turbo charging. Supposedly there is a software update where you can throttle the charging to I believe 600 or 800 watts. I think there are other factors as well that would prevent turbo charging like battery temp for example. Sometimes the AC180 will throw an alarm for grid oscillation if your power is not stable, henceforth why I recommend ensuring grid enhancement mode is on in advanced settings.
@sealy1986 One thing I have noticed with the AC180 I go camping with. I normally charge only Silent mode, but on one occasion I raised it to Standard charge when at 70% SOC. When I checked the SOC a while later, it was 86% SOC and even though it was set to Standard, the charge had throttled back to around 275W = Silent.
I have long believed that if charge is near zero and set it to Turbo the charge rate won’t necessarily be immediately at that high rate. I think it will slowly increase until at least a certain level of SOC. Then as it fills, again throttle back near 80%. Not knowing what happens with the charge curve at each charge setting intrigues me. So, when I have a little time to spare, I’m going to deplete one of my power stations to almost zero, then recharge it to see what actually happens, and, for each charge setting. That’s gonna take a bit of time, lol.
Edit - At least I know set to Silent it will be a constant 270-280W, so only need to do the 2 higher settings.
I finally did a test to isolate the issue. I ran AIDA64 and FurMark to load the workstation to over 300W of usage with the server in sleep mode. In this configuration I don’t have the problem at all the AC180 works perfectly. So it seems that for some reason the EVGA 1000 G2 power supply on the server is causing the AC180 to have this issue.
I have tried it in charging mode Standard or Turbo each with or without power lifting enabled. The same behavior exists in all modes when the problematic server with the EVGA 1000 G2 power supply is powered on and not sleeping. When its sleeping there is no issue at all.
I just turned the server back on and I will attempt to get a picture of the behavior once it goes into charging mode. I did grab a picture of the settings.
I have added 3 screenshots. The 99% percent image was taken about 2 hours before the 96%. The AC180 is plugged into the grid the whole time. There is no DC load or PV input. Also there have not been any power interruptions at all. I live less than 1 mile from the substation so my power is usually very stable.
Just now I put the server wirth the EVGA 1000 G2 power supply to sleep and just after it got into sleep mode the AC180 started charging. I added 2 more pictures that show the charging. The second picture was taken a few minutes later when I retested loading the workstation with FurMark and AIDA64.
By that time the charging had already got to 99% and continued charging. In all the testing done today I made no changes at all to the settings. Also at this time the battery is at 100%. I kept the server sleeping.
Temperature can affect charging rates (i.e. if its too hot) and it is normal behavior for the machine to lower its charging capacity when it is near the top end of the SOC (say 80% or more). I notice this all the time on my portable EB3A unit. It will charge perfectly fine at 195 W from my T200s wall adapter then when it gets to around 95-96% it goes ALL the way down to like 60W or so.
In UPS mode, you are operating as a passthrough, which means whatever wattage is not occupied by the continuous output load is allocated to charge the battery. Constant Load + Charging Watts = Cannot exceed 1440W. So if you have a continuous output of 1000W due to the server/workstation PSU surging due to power demand, the unit will only be able to charge at MOST 440W. Your PSU can supply 1000W continuous but that’s obviously only when subjected to a load. If the server is idle the CPU, GPU aren’t stressed so its likely using say 200W.
A few more interesting notes - You will only receive full 1440W charging with the proper OEM gauge cable. The AC180 needs a full 12A to supply 1440W turbo charging, but a cheap 20 gauge AC cable from a PC will limit it to 8A. 14 gauge can handle the 12A requirement easily. So you are limited to 8X120 OR 960 available charging watts. Assuming that you are using the proper OEM AC charging cable and the continuous output is well within the parameters to supply fast charging, but the charging is still limited, another possibility is “harmonic disruption” from your AC source. Input waveform distortion. Dirty power essentially. Higher wattage PSUs under a lower constant load generate higher harmonic disruption than smaller PSUs. Non-linear loads cause distortion. The AC180 outputs pure sine wave, but if the devices send back too much dirty noise, the firmware may reduce charging load to protect the battery. If you plug in JUST the server and it can maintain turbo charging then the harmonic disruption is low enough, but perhaps the combination of both the 850W and 1000W together is just too much. TLDR - I think your 1000W EVGA is too noisy and its causing your charging to be throttled by the firmware. If the same thing happens and the ONLY thing you have plugged into the AC180 IS the server then the problem is that PSU/server.
Thanks everyone for your help! I don’t have time to look at this now but I will try to get to it tomorrow.