Are there any EB Series models that Bluetti recommends for use as a traditional UPS (always plugged in to 120VAC, short switchover time, reliable 120VAC +/- 2% output with variable input 115 ~ 125 VAC) ?
I have recently been trying to use both of my EB3A devices as a replacement for an APC SUA 1500 (batteries died, don’t want to continue buying more SLA Batteries) and have been having the following problems … which I think other people are also experiencing:
EB3A providing power to [over a 3 day period], constantly plugged in, output load varies from 65W to just under 300W … running two VOIP phones, 1 GBit switch, 1 tower PC with two monitors [usually 120 ~ 200W depending upon activity], 1 Desktop PC [usually 60 ~ 80W] used as a phone line monitor/recorder
EB3A one
one occurrence of ‘overload’ shutdown likely when input voltage went slightly over 125V AC output is shutdown and will not restart until Grid Power
4 occurrences of ‘spontaneous’ power cycling … two attached PCs power off & power back on within 1 second … but VOIP phones and GBit switch are not affected.
EB3A two
3 occurrences of ‘spontaneous’ power cycling of two PCs without any apparent effect on other devices.
2 occurrences of ‘spontaneous’ power cycling of ONLY the tower PC while other Desktop PC continues working … one during the typing of this message.
There seems to be some very short drops (likely 25 ~ 200 MS duration) in the output of both of my EB3A devices when attempting to use them as traditional UPS devices.
I suspect they were not designed for this purpose
… I would appreciate a reply from Bluetti that can help me understand which models are suitable for use as a traditional UPS … or if is possible that both of my EB3A devices are not working properly. Any comments from other users that have the same or similar problem or might have solved this problem would also be welcome.
It is important to note that all Bluetti models regardless of capacity, inverter size, etc. are standby UPS devices. When power is lost, it switches to internal battery via a relay (often 10-20ms). To call them a true UPS, marketing is stretching the truth. To say something is truly uninterruptible, there needs to be a continuous circuit at all times. Incoming AC power is converted to DC then inverted back to AC, all the time. Zero switchover. The problem is a “true” UPS is not cheap. They start out around $800-1000 USD range. So with that said, you are perfectly fine using a basic standby UPS mode, provided you have no need for “critical” equipment, and your existing equipment meets the specifications of the switchover time of the corresponding Bluetti unit. For example on an ATX 3.0 power supply, the switchover is above 20ms when its idle or under 50% load, but if you lost power when it was at 100% load, it needs a minimum of 16ms switchover. Your EB3A can only do 20ms. In this case any Bluetti unit with a 10ms UPS switchover would suffice you. A larger inverter as a buffer for occasionally running higher wattage appliances might be a nice thing to have, as well as put less strain on the inverter since its never near the top end (all the time). So even if you “only” use 300W continuous, an inverter under lower load generates significantly less heat than one running closer to its limit. I own an EB3A and have had nothing but unreliable UPS problems myself. I simply quit using it. The thermals in the unit are flawed to say the least. It tends to overheat a lot. Practically any newer Bluetti unit (Elite series or AC) with an appropriate sized inverter and ideally a 10ms switchover will suffice you IMHO.
Thank you for letting me know. I believe I will have to do the same.
re: Practically any newer Bluetti unit (Elite series or AC) with an appropriate sized inverter and ideally a 10ms switchover will suffice you IMHO.
I am now not sure this is true, until I saw this problem with very short ‘power drops’ I believed the same as you. There is something happening that causes these very short power interruptions that I do not yet understand and would like to understand why they happen so that I might be able to either prevent more occurrences or at least plan to avoid the ‘spontaneous reboots’.
I think there is a bit more to the problem that I described though … for short times I have successfully run several different PCs using either of my two EB3A units … if I pull the plug from the wall, the PCs have always kept running. But over the last few days one of my PCs reboots in the way that seems to indicate a very short loss of power … even though the firmware power management is set to NOT power up on the restoration of power after a power loss … while the other PC connected to the same power plug on the EB3A does not reboot. This makes me believe the ‘power loss’ is very short duration but probably longer than the 20ms transfer time while there is no noticeable grid power interruption to the EB3A. I don’t have good information about what triggers this event though … at first I thought it might be because of excessive voltage on the input for grid power … but haven’t seen enough occurrences to support that conclusion yet.
It might be related to the charging switching … I am not sure but think these ‘very short output power drops’ only happen when the device is charging from 99% … haven’t paid enough attention to be sure yet.
I am hoping that someone from Bluetti will have better insight into why this is happening and can recommend a better choice for a UPS. I just ordered an elite 100 V2 and an elite 200 V2, I am hoping that one or both of these will work … but wouldn’t want to use for either of these for a constantly powered UPS if there is something about the design that could lead to significantly shorter usable life of the device or unsatisfactory results similar to what I am now see with the EB3A … I think a Bluetti engineer would probably know what is happening and why.
You can consider to upgrade your APC Smart-UPS 1500 with aftermarket LiFePO4 batteries. This will eliminate the need of replacing your UPS batteries every 4 to 5 years and will increase the runtime of your batteries as well, depending on which batteries you use.
WARNING
There is risk of fire involved if you do not get high quality LiFePO4 batteries that are designed to be used as drop-in replacement for your SLA batteries, to be used in series, to be charged by your UPS SLA charger.
WARNING
Read the full video description, especially the part of avoiding low quality cheap LiFePO4 batteries from Amazon etc.
This is my video of my setup. I use (expensive but high quality) European made batteries by PowerTech systems. I use this besides my Bluetti AC300 system. I was unhappy about the AC300 constant charging/discharging when used as UPS and it’s high standby power usage in UPS mode.
I now use my APC SUA1500i as UPS and have my AC300 with a beefy B300 batteries as offline backup. The APC will handle any power cuts and when the power cut lasts longer I can just turn on my AC300 and hotplug my APC ups into my AC300 for a 16+ hour battery backup time.
I also use my EB3A as a replacement for a UPS that the battery died (don’t remember the model). At first, I had a number of issues, mostly where it would overload and stop working, sometimes multiple times a day.
Based on another thread, I requested a firmware update, and it fixed the issues. My EB3A has been running non-stop with no issues for over 6 months (knock on wood).
When requesting the upgrade, be sure to include @BLUETTI_CARE in your post so they see it. Also include the serial number of your EB3A.
I did try to find suitable LifePO4 batteries but was not able to find any in Canada (where I am) … I did use some 7AH LifePO4 batteries for a smaller APC Smart UPS and it seems to be working fine for about the last 10 months or so. I’m not willing to buy anymore SLA batteries now.
Please tell me what brand & model of batteries did you use for your APC SUA1500 … I might be able to find out if these are available to me. I would like to be able to re-use the 4 APC SUA1500 units that I still have and not using because of dead batteries.
Thank you, Richard. I did sent a problem report to Bluetti by filling in the ‘after sales’ support request form on the local version of their website … if I don’t get a response in the next few days I will try posting (with the @Bluetti_Care data string included) here again.
Has your EB3A been getting unusually warm … some info on this forum suggests that leaving it plugged in all the time might cause it to overheat.
WARNING 
