AC500/B300S - SoC sudden drops, with data logs

Product Discussion BLUETTI AC Series
1

I have an AC500/B300S setup, charging from PV panels. I have three 400W panels connected to each of the AC500 DC inouts, and another panel connected to the DC input of the B300S.
I periodically discharge the battery from 90% to 20-30% at 2200W to charge my car.

I am seeing all sorts of odd behaviour - S0C dropping from 20% to 0% over the course of 1-2 minutes, sometimes shortly afer discharge stops, sometimes several hours later, usually resulting in a “D-Bat” drained alarm. I have also once seen a “BMS Overvoltage” alarm.

I have seen other reports of sudden SoC drops, but I have been logging SoC, battery voltage, PV input etc. via the Bluetooth interface. so I have some measurements which might help shed light on what is going on

There is clearly something very broken with the SoC calculation - hopefully these logs will help track down the bugs.

I have also seen it get into a state where it does not charge frem DC-in despite SoC being shown at 25% and vattery voltage at 52V, and only disconnecting the PV and power-cycling the AC500 would recover.

Versions :DSP 4047.30 ARM 4048.0 HMI 6052.034 BMS 1022.08

The full logs can be downloaded here : `Here

Here are some excepts (not sure why some of these are showing in bold)

20:40:28 SoC% 37 V_bat 49.9 W_in_PV 0 I_bat 474 1 W_out_AC 2230
20:40:49 SoC% 37 V_bat 49.9 W_in_PV 0 I_bat 474 1 W_out_AC 2230
20:41:09 SoC% 36 V_bat 49.8 W_in_PV 0 I_bat 474 1 W_out_AC 2232
20:41:29 SoC% 34 V_bat 49.7 W_in_PV 0 I_bat 476 1 W_out_AC 2233
20:41:50 SoC% 30 V_bat 49.6 W_in_PV 0 I_bat 474 1 W_out_AC 2230
20:42:10 SoC% 26 V_bat 49.5 W_in_PV 0 I_bat 476 1 W_out_AC 2229
20:42:30 SoC% 23 V_bat 50.6 W_in_PV 0 I_bat 0 0 W_out_AC 0 SoC sudden drop
07:12:36 SoC% 0 V_bat 51.7 W_in_PV 0 I_bat 3 0 W_out_AC 0
07:12:56 SoC% 0 V_bat 51.7 W_in_PV 0 I_bat 0 0 W_out_AC 0

13:11:43 SoC% 78 V_bat 53.1 W_in_PV 0 I_bat 0 0 W_out_AC 0
13:12:03 SoC% 78 V_bat 53.1 W_in_PV 0 I_bat 0 0 W_out_AC 0
13:12:23 SoC% 78 V_bat 53.9 W_in_PV 610 I_bat 99 0 W_out_AC 0
13:12:44 SoC% 82 V_bat 55.9 W_in_PV 1252 I_bat 252 0 W_out_AC 0
13:13:04 SoC% 85 V_bat 56 W_in_PV 0 I_bat 0 0 W_out_AC 0 SoC rising with no input
13:13:24 SoC% 89 V_bat 55.1 W_in_PV 0 I_bat 0 0 W_out_AC 0
13:13:45 SoC% 90 V_bat 54.7 W_in_PV 0 I_bat 0 0 W_out_AC 0
13:14:05 SoC% 90 V_bat 54.4 W_in_PV 0 I_bat 0 0 W_out_AC 0

15:30:37 SoC% 26 V_bat 49.8 W_in_PV 656 I_bat 337 1 W_out_AC 2247
15:30:57 SoC% 23 V_bat 50.1 W_in_PV 1204 I_bat 233 1 W_out_AC 2243
15:31:18 SoC% 19 V_bat 50 W_in_PV 1205 I_bat 233 1 W_out_AC 2242
15:31:38 SoC% 19 V_bat 51.3 W_in_PV 304 I_bat 64 0 W_out_AC 0
15:31:58 SoC% 19 V_bat 51.6 W_in_PV 594 I_bat 117 0 W_out_AC 0
15:32:19 SoC% 19 V_bat 51.8 W_in_PV 721 I_bat 141 0 W_out_AC 0
…2 hours later - maybe coinciding with PV dropping ?
17:14:37 SoC% 19 V_bat 52.6 W_in_PV 52 I_bat 11 0 W_out_AC 0
17:14:58 SoC% 18 V_bat 52.6 W_in_PV 53 I_bat 9 0 W_out_AC 0
17:15:18 SoC% 18 V_bat 52.6 W_in_PV 51 I_bat 11 0 W_out_AC 0
17:15:38 SoC% 17 V_bat 52.6 W_in_PV 50 I_bat 11 0 W_out_AC 0
17:15:59 SoC% 14 V_bat 52.6 W_in_PV 48 I_bat 9 0 W_out_AC 0 SoC sudden drop with no load
17:16:19 SoC% 10 V_bat 52.6 W_in_PV 48 I_bat 9 0 W_out_AC 0
17:16:39 SoC% 7 V_bat 52.5 W_in_PV 46 I_bat 9 0 W_out_AC 0
17:17:00 SoC% 4 V_bat 52.5 W_in_PV 43 I_bat 8 0 W_out_AC 0
17:17:20 SoC% 1 V_bat 52.5 W_in_PV 40 I_bat 8 0 W_out_AC 0
17:17:40 SoC% 0 V_bat 52.5 W_in_PV 39 I_bat 8 0 W_out_AC 0
17:18:01 SoC% 0 V_bat 52.5 W_in_PV 36 I_bat 8 0 W_out_AC 0
17:18:21 SoC% 0 V_bat 52.5 W_in_PV 34 I_bat 8 0 W_out_AC 0

Sudden drops in PV input - possibly due to high battery voltage ?
11:36:27 SoC% 50 V_bat 53 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:36:48 SoC% 51 V_bat 54 W_in_PV 633 I_bat 104 0 W_out_AC 0
11:37:08 SoC% 54 V_bat 55.4 W_in_PV 654 I_bat 147 0 W_out_AC 0
11:37:28 SoC% 58 V_bat 56.6 W_in_PV 509 I_bat 26 0 W_out_AC 0
11:37:49 SoC% 61 V_bat 55.5 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:38:09 SoC% 65 V_bat 55 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:38:29 SoC% 68 V_bat 54.8 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:38:50 SoC% 70 V_bat 54.6 W_in_PV 0 I_bat 0 0 W_out_AC 0

11:53:44 SoC% 70 V_bat 52.9 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:54:04 SoC% 70 V_bat 52.8 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:54:25 SoC% 70 V_bat 52.8 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:54:45 SoC% 70 V_bat 52.8 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:55:05 SoC% 70 V_bat 53.4 W_in_PV 22 I_bat 4 0 W_out_AC 0
11:55:26 SoC% 74 V_bat 54.9 W_in_PV 647 I_bat 139 0 W_out_AC 0
11:55:46 SoC% 77 V_bat 56.1 W_in_PV 428 I_bat 53 0 W_out_AC 0
11:56:06 SoC% 81 V_bat 55.2 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:56:27 SoC% 84 V_bat 55 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:56:47 SoC% 88 V_bat 54.8 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:57:07 SoC% 91 V_bat 54.7 W_in_PV 0 I_bat 0 0 W_out_AC 0
11:57:28 SoC% 94 V_bat 54.4 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:57:48 SoC% 97 V_bat 54.2 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:58:08 SoC% 99 V_bat 54.1 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:58:29 SoC% 99 V_bat 54 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:58:49 SoC% 99 V_bat 53.9 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:59:09 SoC% 99 V_bat 53.8 W_in_PV 0 I_bat 6 1 W_out_AC 0
11:59:30 SoC% 99 V_bat 53.7 W_in_PV 0 I_bat 6 1 W_out_AC 0

Sudden rise from 24% to 73% over 5 minutes
15:15:31 SoC% 24 V_bat 55 W_in_PV 650 I_bat/10 152 W_out_AC
15:15:51 SoC% 26 V_bat 55.3 W_in_PV 0 I_bat/10 0 W_out_AC
15:16:11 SoC% 30 V_bat 55 W_in_PV 0 I_bat/10 0 W_out_AC
15:16:31 SoC% 33 V_bat 54.8 W_in_PV 0 I_bat/10 0 W_out_AC
15:16:52 SoC% 36 V_bat 54.7 W_in_PV 0 I_bat/10 0 W_out_AC
15:17:12 SoC% 40 V_bat 54.6 W_in_PV 0 I_bat/10 0 W_out_AC
15:17:32 SoC% 43 V_bat 54.5 W_in_PV 0 I_bat/10 0 W_out_AC
15:17:53 SoC% 47 V_bat 54.5 W_in_PV 0 I_bat/10 0 W_out_AC
15:18:13 SoC% 50 V_bat 54.4 W_in_PV 0 I_bat/10 0 W_out_AC
15:18:33 SoC% 53 V_bat 54.3 W_in_PV 0 I_bat/10 0 W_out_AC
15:18:54 SoC% 57 V_bat 54.3 W_in_PV 0 I_bat/10 0 W_out_AC
15:19:14 SoC% 60 V_bat 54.2 W_in_PV 0 I_bat/10 0 W_out_AC
15:19:34 SoC% 64 V_bat 54.2 W_in_PV 0 I_bat/10 0 W_out_AC
15:19:55 SoC% 67 V_bat 54.1 W_in_PV 0 I_bat/10 0 W_out_AC
15:20:15 SoC% 70 V_bat 54.1 W_in_PV 0 I_bat/10 0 W_out_AC
15:20:35 SoC% 73 V_bat 54.1 W_in_PV 0 I_bat/10 0 W_out_AC
15:20:56 SoC% 73 V_bat 54 W_in_PV 0 I_bat/10 0 W_out_AC

drop from 22 to 0% over 2 minutes - approx 30 mins after load was turned off
17:21:12 SoC% 22 V_bat 52.2 W_in_PV 55 I_bat/10 9 W_out_AC 0
17:21:32 SoC% 19 V_bat 52.2 W_in_PV 52 I_bat/10 9 W_out_AC 0
17:21:53 SoC% 16 V_bat 52.2 W_in_PV 51 I_bat/10 9 W_out_AC 0
17:22:13 SoC% 13 V_bat 52.2 W_in_PV 51 I_bat/10 9 W_out_AC 0
17:22:33 SoC% 9 V_bat 52.2 W_in_PV 51 I_bat/10 9 W_out_AC 0
17:22:54 SoC% 6 V_bat 52.2 W_in_PV 51 I_bat/10 8 W_out_AC 0
17:23:14 SoC% 3 V_bat 52.2 W_in_PV 50 I_bat/10 8 W_out_AC 0
17:23:34 SoC% 0 V_bat 52.2 W_in_PV 52 I_bat/10 8 W_out_AC 0 D-BAT drained alarm
17:23:55 SoC% 0 V_bat 52.2 W_in_PV 54 I_bat/10 8 W_out_AC 0
17:24:15 SoC% 0 V_bat 52.2 W_in_PV 51 I_bat/10 8 W_out_AC 0
17:24:35 SoC% 0 V_bat 52.2 W_in_PV 53 I_bat/10 8 W_out_AC 0
17:24:56 SoC% 0 V_bat 52.2 W_in_PV 52 I_bat/10 8 W_out_AC 0

1 Like
2

Hello,
in order to help you, we first need the technical data of the panels.
How many batteries do you have and how are they connected?
Have you calibrated the system?
Are all cables properly connected and locked in place?
Are the panels connected in series or parallel?
Note that the charging volume at the DC input of the B300S does not affect the SOC because it is not displayed and added.
Sometimes it helps to search and read something in the forum beforehand.

Greetings from Germany

Hallo,
um dir helfen zu können brauchen wir zuerst die technischen Daten der Panele.
Wieviele Akkus hast Du unf wie sind sie angeschlossen?
Hast du die Anlage kalibriert?
Sind alle Kabel ordentlich verbunden und eingerastet?
Sind die Panele in Reihe oder parallel angeschlossen?
Beachte, daß das Ladevolumen am DC-Eingang des B300S den SOC nicht beeinflußt, weil er nicht angezeigt und hinzugerechnet wird.
Manchmal hilft es auch, vorher im Forum etwas zu suchen und zu lesen.

Grüße aus Deutschland

1 Like
3

I did a full charge to 100% and discharge to 0% before I started logging.
One B300S
Panels are nominally 400W, each set of 3 series-connected panels produces around 100V up to about 12A. 2 sets of 3 to the AC500, and one single panel (30v) to the B300S.

1 Like
4

I think you should contact Bluetti’s customer service. Maybe someone can give you some advice.
Unfortunately I can’t.
By the way, I’m interested in how you plan to charge your car with ONE battery.:wink:
Ich glaube du solltest den Service von Bluetti kontaktieren. Vielleicht kann dir ja jemand noch einen Rat geben.
Ich kann es leider nicht.
Interessant für mich ist übrigens, wie du mit EINEM Akku dein Auto aufladen willst.:wink:

1 Like
5

I only need one battery - I will be using an external controller via Bluetooth to automatically turn the AC on at 90% and off at 20%, so the car will charge over multiple charge/discharge cycles of the B300S.

This issue is clearly a software bug, and needs to be passed on to your software developers.

1 Like
6

The guy you replied to isn’t working for bluetti. He can’t pass anything to any developers.

You need to contact bluetti directly via mail.

So either here: Contact Us - BLUETTI

or here: Contact Us - BLUETTI EU

or select the correct country in the top right and then go to Support->Contact.

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