I understand that LiFePo4 can be charged down to 32F/0C, and discharged down to -4F/-20C.
Looking through the AC200MAX manual, I see that it has over temperature protection, but I didn’t see mention of under temperature.
My questions is: Does the AC200MAX BMS monitor the battery temperatures and prevent charging if it’s too cold?
We are about to get very cold (for Texas at least) and hopefully power doesn’t go out, but if it does, the unit will probably get cold. If I wait until it’s above 32F to charge, I have no way of knowing if the internal temp has risen above 32F. I realize if I’m using/discharging it, that might keep it warmer inside, but it would still be nice to know the BMS has a sensor for low temperatures.
I guess the same question for the B230 & AC180.
Yes. Charging will be prevented if temperature gets too low.
Thanks Scott. Is this published somewhere or has Bluetti mentioned it in the past?
When you have a look in the manual where the errorcodes are, there should be a errorcode for “Low or High temperatur”.
I checked the error codes before posting and the closest I saw was “041 BMS Temperature Error”, which is not specific enough to confirm low temp protection.
I also searched the manual for “temp” and while it did find the 041 error, it didn’t find anything specific to low temp protection. I also search for “low”, same thing.
Unless Bluetti responds confirming it has low temperature protection, I think it’s best if I assume it does not.
Its in the owners manual and usually printed on the specifications label of the unit itself
As I mentioned in the original post, I’ve looked in the manual. I’ve looked at the printed manual that came with it, and I’ve looked at, and used the find/search feature on the PDF I downloaded for it from the Bluetti site.
I also just looked at the unit itself as you mentioned.
They all mention the range of temperature it can be charged, but no where does it state it has any kind of under temperature protection if the batteries are too cold.
Look, it’s no big deal if it doesn’t have it. Bluetti never claimed it did. Everywhere they give a specific range that it can be charged. I was asking in case I missed something. I’ll simply make sure they’ve warmed up enough before charging. If I have solar plugged in, I’ll disconnect it on nights that might get too cold so it doesn’t start charging on it’s own when the sun comes up.
Unless you have seen it mentioned in another document, or on an official Bluetti site, it’s probably best not to post that it’s safe to charge outside the temperature range mentioned in the specs. If someone see’s that and tries it, they could damage their batteries.
The bluetti will not allow charging to occur outside the temperature range. Put in in your freezer overnight and try charging in the morning if you don’t believe.
@rgb
I have checked the manual, and indeed, only Over-temperature Protection is marked. I have already reported this issue to the relevant team, thank you for pointing it out. Don’t worry, there is under-temperature protection. Temperature protection already includes over-temperature protection and under-temperature protection. As long as you charge and discharge the machine within the specified temperature range, there will be no problem.
I have a similar question that has not been answered so far in this thread. I have the AC300 and 2x 300.
.
How can we know the internal temperature? Neither the APP, nor the unit display panel report what we are dealing with.
.
Two days ago, also in Texas (SE), ambient temp was around 25°. And with first light, the batteries started charging. I ran a little space heater to warm around the B300 batteries, but they started charging on their own.
.
Yesterday, the ambient temp dropped to 18°…after it had barely gotten above freezing the day before. So, I suspect the internal temp in the batteries was much lower. In the morning, and basically until noon, even through the ambient temp was in the 40°s, the charging had not kicked in. I was able to remote start a space heater, and one of the two B300 batteries started accepting PV of 750w at a time I normally pull 2k. The 2nd battery remained in Standby with a Temp Error.
.
Thanks to @hnymann in another thread, when I got home, I shut the whole system down, and when I brought it back up, charging to the 2nd B300 was back running.
.
Three challenges/requests.
-
Why wasn’t more of the PV input dedicated to charging the single battery? For three hours, I monitored the PV input as it remained consistent at ~750. Why did it not at least get 1200 to the one battery?
-
How can we “reboot” a cold battery remotely after it has warmed up? As it is, I am glad one started charging. But we need the ability to reset or jump start the system so that charging resumes after the temp is high enough.
-
How can we get more data about the internal temperature with the app…or at least on the unit control panel?
Thanks!!
Hi @DrewLoker
for the temperature, take a look at my short video here:
https://youtu.be/FvvCjqBnLV0
You can activate a “secret” menu which shows different values of temperature sensors
greetings
Erik
Wow…that’s interesting…but it did not work on the AC300. Any other Easter Eggs? Not sure why this info is hidden in the first place.
Hi @DrewLoker
Its does work on AC300. Its really important to go the way like i show it in the video.
Data → Battery Information and click 5 times on the upper left corner. This should work for all Bluetti Units with this display
We were below freezing for close to 60 hours, with it dropping down to 12F to 18F/-11.1C to -7.7C for three nights. For those that live in cold regions that probably doesn’t seem to bad, but again, this is Texas. The day after having a low of 12F/-11.1C, we hit 78F/25.5C. I had planned to try charging if it got cold enough and stop it if it did charge , but in the garage where I keep the AC200MAX and B230’s, it only got down to 36.8F/2.6C. Most of the time it was warmer. No room in the freezer since I try to keep it stocked up with food. Still plenty of colder weather ahead, so I might get another chance to try it.
Thanks - good info to know. This worked on my AC200MAX, though the temps at the bottom are a bit different. From looking at your video, the ‘P’ must be PV or the charge controller, and ‘I’ must be the inverter. I’m guessing ‘A’ and ‘B’ are two sensors for the batteries? Anyone know that the ‘D’ is?
I will also confirm that this works on the AC300. Actually, I hadn’t realized it works on the AC200Max too, so that’s nice!
If you use the + and - top left, it should show info for any connected batteries too. Worked for my two attached B230’s.
YES! Thank you for following up and persisting. I tried again and it worked on the AC300!
Now, @BLUETTI , can we please get that info in the APP? As well as a few other things we are missing in the APP.
Thanks!!
@DrewLoker
After confirming with the tech team, the temperature display is for internal maintenance staff and cannot be synced to the app.
Sure…I get that is how you all have had it set up, but we need to know this info. It should not be buried on the device…and it should be available to us in the APP. Like also knowing what PV1 vs. PV2 is producing. I know you all have your priorities, but we could really use more info in the APP. Thanks for your help with this.