I received a new EB3A this week and have set it up in UPS mode, plugged in to AC with a computer (~40-60W) connected to the AC output.
I’ve noticed periodic buzzing every 10-15 minutes or so, which sometimes (but not always) is followed by the fan coming on.
I read similar reports of this both here and on reddit but it they seemed to be older. Is this still a normal issue with these units or are some ok? I like the features of the EB3A but may return it to Amazon due to the noise.
Here’s a video of the noise. It sounds quieter than it is in the video, but towards the end the noise stops and you can hear the difference.
Hi @sean, Generally, when the machine’s charging or discharging power reaches a certain level, the fan will start. The fan will also start when the internal temperature of the machine reaches a certain threshold, and it will shut off once the temperature decreases, which may cause periodic noise.
We suggest setting the charging mode to Silent Mode in the Bluetti app and observing whether the buzzing sound persists. If the buzzing disappears, it may be due to the fan starting because of high load or high temperature.
It seems there might be background noise from the video in the environment. We recommend testing the machine in a quiet, open space while simultaneously charging and discharging. If the machine noise is still loud, we advise contacting customer service for a repair.
Thanks for the reply, I am already working with customer service on this.
For reference, the silent mode makes no difference here (I had already tried that). The buzzing happens regardless. The video is taken in a quiet room with no other noise so all the noise is from the unit. At the end of the video you can hear it go completely silent once the buzzing stops.
I did see suggestions elsewhere to use an external fan blowing into the air vent to help keep the unit cooler so I am trying this at the moment. So far with an external fan I have not noticed the buzzing or the internal fan coming on.
My feedback to Bluetti is to enable an option to keep the internal fan on while plugged in to external power to help keep the device cooler. This could be a firmware update. Otherwise a better cooling system in future hardware designs.
Hi @sean, Thank you for letting us know.
I think our customer service team will help you resolve this problem.
And I have forwarded your feedback to our R&D department. That is very precious advice.
The fan buzz on the EB3A has been a known issue for a long time, as you’ve seen from other posts. The EB3A also has known issues with overheating and failure to deliver the full rated amp output via the 12v cigarette plug. If you still can I’d return it and look for something more reliable.
Sorry for bumping the old post, but I’ve got the same problem.
I just got a new EB3A as a replacement for my previous one which started turning off the AC outlet when reaching 100% charge - which was traced by the official service center to an imbalance between battery cells. Despite this problem, it was actually working very quietly - it never turned the fans on when it was fully charged and in UPS mode. It did emit some quiet electrical humming when it was going between 99% and 100%, but that was very quiet and the fan never turned on afterwards. I only ever heard the fans when the unit was charging or discharging, but never in UPS mode.
Eventually, the unit was deemed unserviceable due to lack of replacement parts and I was issued a supposedly brand new replacement unit.
This new unit, however, is buzzing like a water pump for half a minute before the fans kick in, and they do kick in loudly and annoyingly often - every hour for sure, sometimes even after just 20 minutes. I noticed the firmware version is different in the new unit (ARM v2053.08, DSP v2052.11, no IOT version) and an upgrade is not available.
@BLUETTI_CARE is this normal for this model? If so, why the noise and fan behavior of two units is so different? If it is something that can be fixed by a firmware update, I would greatly appreciate that.
I have tried Silent charging mode in the app, and in my opinion it makes the noise and the fan kick in even more often than in Standrad mode.
Hi @Ur-Quan, we have a new ARM firmware available for push, but we are not sure if it can fully resolve the issue.
If you are willing to try, please provide the SN code of your EB3A so we can push it for you.
Hi @Ur-Quan, thank you for your confirmation.
I have applied to upgrade your system to our IT department. If the new firmware is available, they will complete the push within 24 hours.
Please upgrade the firmware tomorrow. Please do not load any device when upgrading it.
Please let us know if it works.
Hi @BLUETTI_CARE
Thank you very much, I have just received the new firmware and upgraded my power station to ARM v2053.09.
I will observe the behavior over the next couple of days and let you know if there’s any improvement.
Thanks again!
Hi @Ur-Quan, thank you for your update, we are glad to hear that!
We hope everything goes smoothly from here!
Please don’t hesitate to reach out to us if you need our help.
Hi @BLUETTI_CARE
I have been observing the station’s behavior since yesterday. Unfortunately, the issue is not resolved.
The station still has to turn on the fans regularly even when it’s in UPS mode at 100% and neither charging nor discharging. Also there is still a half-minute of electric pump-like noise before the fans start, so that has not changed either. I’ve read that it could be caused by a fan controller, but I’m not sure if that’s the case.
When the fans start, it seems like they start at a lower speed, and ramp up more gradually, so the noise is not as jarring as it was before. So there is a slight improvement in that area, probably the fan curve has been edited in the new firmware.
However, overall the station is, unfortunately, still pretty noisy compared to my original one.
Not sure if anything can be done with that, but if and when a new firmware becomes available, please let me know!
Hi @Ur-Quan, thank you for your feedback. We have passed it on to our technical team. We cannot fully control the fan speed manually, as it is automatically adjusted by the BMS based on the internal cell temperature and operating power.
We will contact you if new firmware becomes available later.