AC200MAX Battery Temperature Display

Does the AC200MAX have a battery temperature display feature? I see that there is a 041(?) error message that alarms when the battery temp is at 0 C or lower when the user attempts to charge the battery pack, but I can’t find on the touch screen the actual battery temperature. That would be helpful for remedying the situation by warming up the AC200MAX before charging is necessary.

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Hi @mrp55net , Please leave the machine for a while and see if it still reports errors.

Thanks for the reply. I’m not reporting an existing problem. I am looking for the AC200MAX’s battery temperature on the touch screen display. If, currently, there is no access to the AC200MAX’s battery temperature on the touch screen display, there should be one. It would be very convenient in areas where a solar generator with a LiFPo battery system can easily be placed or found in a site where the generator is at a below-freezing temperature. Since the operating discharge temperature is well below freezing, the user can then make decisions based on getting the batteryABOVE freezing before before attempting to charge.

I have found that pressing (Data) and then (BMS Maintenance) and then pressing in the upper left corner of the screen 5 times. It should beep with each press I think there is a time constraint between presses.
You should see a screen that shows cell voltages and some temperatures. Temps are labeled (A B D P and I) no idea which is what.
May have to press the + - buttons near the upper left to get the display refreshed.

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Thanks, Andre! One would think that with the number of AC200MAXs sold for four-season use that Bluetti would make it easy to display the battery temps. Simply relying on the BMS for a charge-no charge status isn’t good during winter. Clicking on the display at different temperature ranges might work in the meantime.

Best regards, Mark

Thanks for the tip Andre on how to display cell temps. Cheers

I should say the existence of and how to get to that screen was something I read about on this or some other forum. I think it was in relation to the AC500.
Given the amount of information packed onto that screen and how it is accessed I am guessing it is intended for engineering diagnosis.
Hope it does not go away with future revisions.

Yesterday morning was almost clear sky just a very light high altitude haze, here in northern Wisconsin.
The 200Max is for portable use and backup to the main PV system, 100 percent off-grid.
In the morning Max was at about 70%, I was able to catch it at 99% and watch the cell voltages as it finished the charge.
Cell voltages are a “visual” average of the 16 cells.
Charging at about 700 Watts voltages came up to 3.48 ±0.015.
Then charging dropped to about 250 to 300 Watts and cell voltages dropped to 3.3 to 3.4.
Then they slowly, 5 to 10 minutes, came up to 3.58 -+0.020 still at the lower charging wattage, the sky had not changed so more power was available.
Then charging dropped to 0 and over the next 10 to 20 minutes cell voltages dropped to 3.33 with an occasional cell flickering to 3.32.
DC and AC outputs were turned off thru the entire process.

I would say it looks to be a good compromise between Max storage and cycle life.

Then I put a load on and took it down to about 95%. I then let it change back to 100%, cell voltages stayed right around 3.33.