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    JK BMS APK 4.16.3 new feature.

    Hi, I just downloaded the latest apk, and I noticed in the screenshots this interesting feature: "Pre-discharge". Despite the label text, could it mean a pre-charge of inverter caps before turning on? The option doesn't appear when I run the apk, so maybe only for newer versions of the BMS...
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    JK BMS precharge adequate for Conext Pro 6.8KW?

    Hi, I ran in to this pre-charge problem with my new 11kW inverter, the original 5kW is OK. The JK BMS shut down immediately on "Short Circuit" protection. I did a bit of searching, and found a cheap and easy method by using 2 x 24V globes in series. These work great, they glow bright, then...
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    JK bms fast(er) SOC learn

    Hi, I have a laptop & phones (use scrcpy to view phones over USB or WiFi) near the battery banks, so I can remotely connect to the PC with Remote Desktop (or Teamviewer or UltraVNC). dRdoS7
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    New parameter in JKBMS ?

    Hi, Are you still using the same apk version? Mine is 14.15.3, and dosen't have those "Battery" readings. This looks like it measures the total battery, not individual cells, but question is why they are the same initial settings as the Cell OVP & OVPR. dRdoS7 EDIT: I just updated to...
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    Neey Bluetooth Problem

    Hi, Just installed my Hankzor Balancer, and ran into the same problem of the NEEY apks not scanning the balancer. Downloaded the *apkpure version and it scanned it OK. I was stumped for the password, then tried 123456 (JK BMS for Config screen IIRC), and that worked. Thanks for the help. dRdoS7
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    JK bms fast(er) SOC learn

    Hi, Quick error correction & update: The capacity they dropped to from 250Ah was 247.5Ah, not 245.7Ah. Seems that they increment in 2.5Ah steps now for some reason. I have V4.9.1 on one phone, and V4.15.3 on the other. Don't know when they changed, as they used to increment in 0.1Ah steps in...
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    JK (JiKong) RS485 interface wiring

    Hi, Sadly my last PC with a serial port died recently. So all I have are a few unused Serial to USB cables (various chips), don't know if they are suitable. I do have serial cables which I can cut one end off, and put some pin sockets on the end of. I bought an RS485 with each JK BMS, and an...
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    JK (JiKong) RS485 interface wiring

    Hi, Does that mean I could connect those to a serial cable? I was not able to get my RS485 -> USB working with a PC, this would be simpler (as well the fact it might actually work) as I have a few old serial cables lying about in boxes of PC stuff. Thanks, dRdoS7
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    JK bms fast(er) SOC learn

    Hi, Interesting. I tried this today as my 2 banks (1 old, 1 new) were both out of wack. I have 280Ah cells in each, but have the BMS each set to 250Ah. Over the last 3 weeks or so, one was only going to 247.5Ah, but it did go to 250Ah, only to drop back to again shortlty after. The other goes...
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    Cell voltage at dangerous levels

    Hi, As long as the inverter &/or charger is happy, it doesn't matter. Mine is 18 cells LFP. I can go down to 15 cells, as well. Handy if a cell or 2, or 3 go bad. dRdoS7
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    What Size BMS do I need 12S7P 48V 5000W Inverter

    Hi, 7 x BMSs sounds very expensive! What's the voltage range of your cells? Split your 84 cells into 2 or 3 strings. You'll be able to run off only 1 if required. You didn't say what voltages your inverter will handle. My original 3kW, could run at 60V (62V trip). I can recommend the...
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    What Size BMS do I need 12S7P 48V 5000W Inverter

    Hi, Have you thought of using 14S6P? You could split it up into 3 or 2 banks of 14S2P or 14S3P, so you'd only need 2 or 3 BMSs. Gives you some redundancy. Depends if your inverter will handle the higher voltage. I use an 18S with my LFP cells, my MPP Solar inverter will handle 66V, 64V max...
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    Is there any need for BMS / Charger / Inverter comms?

    Hi, Interested in whether there is a need for communication between these devices. I have no comms, and my system works. As far as I can see the comms tells the other devices what the battery is doing so they can terminate charging or discharging. Is there another function? dRdoS7
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    BMSes that can handle extended operations in a partial state of charge?

    Hi, The Heltec (JK BMS) I have will accept .002V (IIRC) cell differential. I use .006V. There is also a start/stop voltage, but I can't remember what it's set at. Probably ~3.35V. The OP quote #4, was concerned that the BMS shutting off charging, may cause failures. I haven't seen this...
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    BMSes that can handle extended operations in a partial state of charge?

    Hi, OP contains a reference which states that cells in a continual partial SOC may become unbalanced (3rd quote), and next quote (#4) explains what may occur when charging. Apart from possible internal losses, the only way know in/out of an individual cell is to measure it, can't rely on it...
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    BMSes that can handle extended operations in a partial state of charge?

    Hi, I see that book was from 2015, so maybe the BMSs now available, weren't. One of these?: https://diysolarforum.com/threads/heltec-jk-200a-smart-bms-with-2a-active-balance.17831/ Active balancing, many balancing settings to adjust to suit your needs. There are probably many more suitable...
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    17S BMS for LiFePO4?

    Hi, If you're still looking, I have one of these: https://diysolarforum.com/threads/heltec-jk-200a-smart-bms-with-2a-active-balance.17831/ I have 18 cells, but it can handle up to 24 cells, and down to 4 cells with a 12v booster (so I have read). My MPP 5048 can charge to 64V, so I wanted to...
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    ENJ Power for Heltec/JK BMS

    Hi, I haven't needed to do anything on the phone, once TV was installed and running. I use it on a 10" tablet as well. Only time it doesn't work is when the phone's gone flat.:oops: Did you install TV Host? dRdoS7
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    ENJ Power for Heltec/JK BMS

    Hi, Have you tried Teamviewer? It's free for personal use. Good remote access over the internet, can be used via LAN too. There's also scrcpy, but that would only work on a LAN. dRdoS7
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    420Ah Cells on Aliexpress!?

    Hi, I may have miscalculated, but the capacity increase from say EVE 280Ah is 50%, the volume increase is 11%, and the weight increase is 4% (rounded up). What are the chances? Maybe their size/weight specs are incorrect (IE. Copy & paste from another cell description?) There was a guy...
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    ENJ Power for Heltec/JK BMS

    Hi, Only need to take action on the phone the first time with scrcpy. Once TV Host is installed on the phone, and added to the account, no more action, usually, is required. I have the RS485 from JK, and a USB adaptor, but haven't got around to setting it up. dRdoS7
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    ENJ Power for Heltec/JK BMS

    Hi, I'm running the ENJPower app on a Huawei Y7 which has Android 7. Remote via a local Win8 PC using scrcpy or Teamviewer (depends which one pi$$es me off the least - currently scrcpy is the better). App loses the BMS at least once a day, but only needs a rescan, usually. Both remote progams...
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    JK-B2A24S20P BMS Verify Password to enable settings change

    Hi, I'm not at home, but if you don't have a user manual, one can be downloaded via links on this forum. You may need to try a few before fiinding one with details. If all else fails, do a Factory reset. Write down, or screenshoot your current settings first. dRdoS7 PS. I don't bother...
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    MPP Solar + BMS communication/control

    Hi, I have an MPP inverter & a JK BMS, no communication between them. Works OK for me. Inverter limits are set inside the BMS limits. If there's a cell/battery problem, the end result is still no battery power, whether they communicate or not. It's either: "I'm empty, bye!" Or: "I'm nearly...
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    LiFePO4 Voltage Chart?

    Hi, It really has no meaning except for relationship between various cell voltages, and what that would equal for the different pack voltages. Someone probably divided up between 2.5V minimum, and the 3.65V maximum for LFP. Looking at a graph for LFP, you'll see that 3V is around 9% SOC, but...
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    Heltec (JK) 200A Smart BMS with 2A Active Balance

    If he's going to use 2 cells from the same pack connected to the BMS, I hope he takes a video when he does it.
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    LiFePO4 Voltage Chart?

    Hi, The ">" should have been a "<". Good thing I'm not a Rocket Surgeon! dRdoS7
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    Another Top Balance Screwup

    Hi, The old adage about leading a horse to water? You're wasting your time trying to stop people making mistakes. Besides, that's how to learn lessons, weed them out, and advance the rest. dRdoS7
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    LiFePO4 Voltage Chart?

    Hi, I am on that forum too. No Float Bug fix for the MG sadly. I'm pretty sure the Error #8 isn't fixed. There is an external 08 "fix" (isolates the PV if it's >70V), for which I have bought the main part, but have yet to go to an electronics supplier for the other minor parts. Have been...
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    LiFePO4 Voltage Chart?

    Hi, I would have thought if it's counting amps, it should be OK. What efficency are you using? My Classic SCC is set at 98%. Over the last 3 months, the measured eff. is 98.5%. So, if I'm right, there's slightly more going than is it's displaying. The BMS I have also counts, but is always less...
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    LiFePO4 Voltage Chart?

    Hi, Could you set the capacity lower? Maybe alter the settings at which it decides to reset the Ah/SOC to 100%? The BMV measures Ah, so you'll probably be able to tweak the settings to get what you want/need. The BMV in my caravan used to reset too soon, so I changed the settings, and it's OK...
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    New 2A Active Balancer with BMS Function won`t run

    Hi, I probably should have quoted something. I was musing on the 3 threads above mine which are discussing how to "boot the BMS" once it's all wired up. Thanks, dRdoS7
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    New 2A Active Balancer with BMS Function won`t run

    Hi, I've often wonder why we need to do this. Why didn't they just have it turn on when connected? Or even put in a On switch? dRdoS7
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    Nickel Iron Batteries

    Hi, One thing I didn't see mentioned was making distilled water. Lots of it. Also, refilling/topping up between cycles. I saw >80% efficency, but only when charging to a lowish voltage, not when charging to a voltage which creates lots of hydrogen. Efficiency dropped to about 50%. I guess...
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    Dongguan Lighting: Purchase 280AH LiFePo4 cells. Purchase & Review

    Hi, It would, hopefully, prevent more getting damaged. The grub screws/studs go further into the terminal, so there's a bit more thread being used. dRdoS7
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