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That's exactly why I asked. So my current workaround to achieve this is by disabling charging current to 0 when exporting to grid.

Will Charge Last feature be ever offered for LXP SNA 5k ?? I live in an area with frequent power cuts and I'd like my battery to be charged only when powercuts happen.

Far more important is to cover them with a tarpaulin or something. No light falling onto the panels, no degradation. Additionally prevents unwanted dust from accumulating. You can leave the string connected as it is. That way you will have easier time preparing them for use when needed.

They communicate with each other over RS485 but can communicate with the AIO using both CAN/RS485. Then your best bet would be CAN. It is very easy to DIY, plus the various protocols are already very well documented, tested. JK-BMS using UART/BLE and using CAN. Try reading through this and...

Thank you for taking the time to meticulously document everything for others. Looks like we need to explicitly state everyone to keep everything updated beforehand.

I have been opening (and destroying) stuff ever since I was a 5yo child. I was privileged to have access to an entire bag of tools to play around. But, even then if you had asked me this just four years ago, I'd have no clue. All this time, I simply relied upon; if it's a flat screw, then flat...

Yes. This should be your CAN Tx and Rx GPIO pins. This is where wires coming from JK-BMS go. Tx-Rx and Rx-Tx. You can always swap the pins in software if it doesn't work in the first try.

I can speak for my Luxpower unit instead, Initially, it usually involves changing battery mode from Lead Acid to Lithium with the CAN protocol to use. The inverter then reboots automatically.

This file is doing exactly that. https://github.com/Sleeper85/esphome-jk-bms-can/blob/main/ESP32_LFP_BLE_jk-bms-can.yaml Connect to a JK-BMS with BLE, send that data to the inverter over CAN. And all this while being connected to your home WIFI and reporting sensor entities for HA. And one can...

There is already UART+BLE hybrid version and it is fully functional in my own home for two months now. The approach to avoid collision is to poll sensors common to both interfaces only once. For example, battery voltage is common to both UART and BLE. in a hybrid file, if you're polling voltage...

Yes yes. But one esp32 can already do both functions at once. Report data to home assistant. Connect to BMS over UART, send data over CAN and also fetch data over BT. Four things at once, actually. They're really that powerful !

I live in an area with frequent power-cuts so I can't even imagine this disabled.

One thing I can tell you it is not a battery specific problem. Rather something on the AIO side. I have noticed this too with DIY battery and LXP SNA 5k. EG4 units are also based on the LuxPower units. So we both are observing the same behaviour. Here is my HA history showing constant power...

Battery voltage STILL IS the primary indicator of whether a battery is charged or discharged fully. It is only in-between that we struggle when it comes to correlating voltage with SOC. But as long as approximations are good, hardly anybody cares. Why should we, when we know that voltage is the...

Any voltage between [3.65 V to FCV] (which I'm taking as 3.37V) is acceptable target bulk voltage in the model. I personally use 3.525 V/Cell Are you really sure you read 5 pages deep into the thread?? :cautious: I am repeating this again. Unless you go and put the effort to understand what is...

Smart! Take your best Voltmeter, capable of highest precision and measure the FCV of a cell, with and without a resistor in series. Entertain us on a video for everyone to see. Let's face the physical reality together. Proportionality only applies to a two-way street. Add a resistor in series...

This is one such option. https://github.com/celsworth/lxp-bridge There are too many common things between 6000XP and LXP units. I assume the WiFi dongle and its interface to be mostly identical. I personally do not have an EG4 unit, but this can work with a bit of tinkering.

I can take two identical cells with same FCV. and connect them in parallel as depicted. The capacity of the combined cell has doubled, The effective IR halved, but the measured FCV or any characteristic voltage for that matter has to be the same. Basic sanity check !! Might as well cite one...

I have a first hand experience in this well before even authoring this guide. What I have realised during the last four months or so is that Float value of LFP is even lower than my already very conservative values in this thread. I now use 53.4 V and still cycle what I like to assume 98% of my...

Now that I am aware of your earlier work on charge termination I would like to read up on them.

Any LFP Cell with modern chemistry when fully rested after a full charge will have a FCV hovering just above 3.37 V. Temperature do affect this but only slightly and that's the simple reason I am not taking that EVE data seriously determining FCV with just 5 minute rest. At my place, summer...

That may be a language barrier. Take a cell, and subject it to full charge (take note of the temperature & misc. Env conditions). Then let the cells rest until the terminal voltage stabilizes. Cell manufacturers usually standardize this time for new cells as 30 minutes. Plot terminal voltage...

Here you admit you're prolly not grasping "my method" . Further clarification, it is not something that I invented in the first place. The Nordkyn article referenced is a mandatory reading BTW. Then you go on and say this. And this. I too am happy to engage in such a discussion. But when you...

I have already seen the PDF you sent. Testing methodology, description of procedures, anything ?? that will help me (or anybody else) verify this on their end. Otherwise it is just blind data that I don't even know how to replicate on my system.

You can always inspect the source code here at https://github.com/Sleeper85/esphome-jk-bms-can/blob/development/packages/smart_bms_cutt-off_logic.cpp Before I am in a position to say anything, I want to know how was this FCV figure determined ? Standard charging model according to EVE...

Thank you for mentioning the crucial "discharging the cells in increments, allowing for rest" part. Many people here routinely love to "prove others wrong" with basic SOC- OCV curves that were not made with discharging cells in increments and allowing for battery rest in-between . I can only...

This screen I suppose you're talking about?? Inverter Firmware update ? This option (and many more) is likely to be exposed when you use the LOCAL CONNECT option in the first screenshot. Your phones needs to be connected to the Dongle Hotspot for this to work.

I wouldn't mull over some decimals of KWh a day in exchange of the convenience and peace of mind it brings.

Don't worry about that small of a number. This I think has to do with fluctuations. Every time a dip/fluctuation occurs, some energy flows in from the grid before the Inverter has time to respond and adjust.

Each ESP will have their own IP addr. and thus will act as its own information server. You need to something to aggregate the information coming from multiple ESPs and present them on a single web dashboard for you. Something more knowledgeable than me can chime in this regard.

Check the PV string voltage with a multi-meter where they connect to the inverter input terminal (after breakers and protection devices). It should correspond to the voltage displayed by the inverter. If not, contact support for repair/replacement.

Sounds like a job for Arduino, ESP32, RPi Pico But my recommendation would be going with ESP32 because they're far more versatile, capable, faster while being cheaper and easier to program.

The BMS can be programmed to accept a charge/discharge current limit. If the charging current exceeds the set limit, the BMS will just cut-off. The BMS never actively regulates the current going into the battery. That is the job of your SCC. Your MPPT controller should automatically regulate the...

CANBus and RS485 are the only two dominant and preferred modes of communication. Most rack batteries come built-in supporting both. Source: https://luxpowertek.com/wp-content/uploads/2023/11/SNA-3-6k-user-manual.pdf There is no need to bother with fragile fiber. There is no need for high...

It just dawned on me, May I ask what framework is everyone using? We recommend the esp-idf framework due to its stability. I also said the same. Basically, new users should use DEBUG logging initially to debug UART or CAN pin issues. Once, everything is up and running they should return to a...