The lack of testing in such a critical piece of equipment is what scares me the most. They literally let their end-users test a product that can theoretically kill someone if it has a bug.

BMS= Safety device . Not proving out Safety software is an unforgivable mistake in my opinion too .

I had a good laugh when you said "recall"....from China? Surely you jest! 🤣 If the default setting was to LiFePO4 it would have only pissed the Li-ion users off but not been unsafe. In ESS use they may never get turned off, but yes, it's a rather dangerous problem

You are right, it is a fatal bug and it should not happen. But in general I'm absolutely happy with their BMS in the past. Years of positive experience, starting and running for ever without any problems. This error comes ONLY with the brand new inverter BMS and they will fix this within the next days, they said to me in person. So, everyone knows, it is brand new and following Andys channel, we all saw the problems with the older SW versions. Yes, no excuses, this should not happen. But it happened. Anyway, I'll keep on using JK-BMS, because they are still the best for our purposes. Once the community is happy with the new inverter BMS and more long term experiences will be available, it will be again a great BMS for the next years, I'm sure!

thank god I only bought one at the time :-) sell it used, take a solid BMS * n BmS then you have time for other things and everything will be fine :-). Happy New Year ☺🤗

Andy, Thanks to you for your video's. I have watch so much, you must graduate me, with a degree in battery's. I have gone on and build 14 battery's to date. these is for the 4 by 4 overland community's and the offroad trailer community's here in Africa. Your comment on the JK BMS is disturbing. what do you recommend as alternative ? 4 to 16 S systems. we use 280 Ah cells.

If you do not use the newest inverter BMS, you would not have any drama.

Aye, I made a point to call out your community as well in crediting the source. It's one of the very best things with youtube; The community brings knowledge and resources to the table we couldn't get otherwise. I really hope this was caught soon enough that no one out there actually lost their cells to this bug.

You're missing the point, this isn't an isolated issue, it's just the most egregious in a long line of questionable business practices.

True community Teamwork 😊

They really fix the "reset" problem or they just changed the LTO to LFPO default setting after a unwanted reset ?....

@@sebydocky5080 The reset and the default values 😊

My understanding is that it resets to LTO now, not LFP, but still that's much safer. I am glad it's fixed for those who bought it, but for me, for the reasons I explained in this video, I still don't trust them anymore.

@@TheDigitalMermaid JK note on their Website for the change: "Change the default configuration parameters to lithium iron to improve security."

@@michaelwessel2983 Ah, ok, good to know.

Older models you've used and tested are probably going to stay fine. The reason I felt I needed to make this video is because you never know what you're actually going to get from JK when you order. Maybe you'll get a good and reliable BMS, maybe you'll get one that could destroy your batteries. It's not a risk I can recommend anyone else take.

Don't overdramatize. Jk BMS are still the best of the budget ones and the speed they fixed this flaw is remarkable. Additionally use a BMV712 as independent last resort solution and something like this won't destroy anything in your system. Yes it should never happen but did...difference they stood up and fixed immediately. Fu.. up always happen, the difference is how and if you even fix it. This compared to many other company incl expensive victron that is not fixing anything or with a huge delay. Victrons 100V range of MPPTs for example the remote steering is hot=on when the remote cable gets disconnected due to any reason. Absolute noGo in EE and a major design flaw they don't fix since 5 years, the phönix shorepower charger 50/1/1 gets over 70 degrees hot but eg cable rating in boats and RV outside the engine room is 60degrees Celsius due to ISO standards...victrons answer was installed in engine room or change cables, 75 degrees is normal..really???...the dealer I bought agreed with me and took it back in the end.

@@chrisr819 How would the BMV712 save a cell from overcharging with this flaw? It can't see the per-cell voltages. As I explained in the video, it's not just this issue, it's a long line of problems with this flaw being just the straw that broke the back. I can understand why people will still choose to use JK, and that's fine. Notice that I didn't say "don't use it", I said "I no longer recommend them". I chose my words carefully. Every one of us has to decide where our comfort level is, and I have mine. JK crossed it, and this being my channel, I felt I had to say something. I've shown JK BMSes in use in my project for 2 years now. If someone saw that, and figured if I used them, they should use them and then they had a problem, I would feel terrible. So for me, my project, and my risk tolerances, _I_ don't recommend them anymore. I'm not overdramatizing, I'm speaking my opinion.

Maddie the BMV712 has 2 measure curcuits so you can set it up as midpoint monitoring that means it measures one half so 8 cells 1-8 together versus cell 9-16. So if you have a runner eg 200mV in cell 10 then half 1 is eg 8x3.4V=27.2 versus 7x3.4+3.6v 27,4V and if you set thershold to 150mV then the BMV712 triggers the relay output to shut off. I take a breaker with trip coil, you need a battery fuse anyhow so the BMV712 connects to the trip coil of the breaker and battery disconnected. This is a requirement by ABYC and if you don't have it in US then you won't get insurance or if a claim happens they deny coverage and most likely cancel your boat policy. In an event like JK BMS all cell will go to 4.2V×16 and if your bank has 50mV deviation then the worst that can happen that 3 or 4 cells hit 3.7V while others have 3,55-3.6V and then the HVC voltage of 16x3.65V is reached and BMV trips the breaker. If you have bigger deviation (which you shouldn't have in 1p16s when they are top balanced and normally taken well care by BMS) then the midpoint monitoring trips the breaker. Like this no cell will be damaged. It cannot work on cell level of a single cell but its good enough to protect the bank from desaster events. And again ypu are obliged to have an independent last resort sountion due to ABYC doesn't matter which BMS you run and that for a good reason. With breaker with trip coil you have no additional contactor in your system, just a 2nd method besides a normal fuse has to disconnect it. I mainly use ElectrodacusBMS as i don't like contactors but also no mosfets based BMS as i often use bank as hybrid starter and house and the inrush or surge currents of a motor destroy the mosfets over time, especially if they are not matched and calibrated which for the price JK offers their BMS (as nearly all other chinese mosfet BMS) is simply not possible to do. So if a motor sizes the surge can be easily quadrupled and that kills eg one fet of your 10, BMS still works but with 9 that ahve to carry the current but because unmatched they do 't switch in the exact same moment so 1 or 2 fets have to carry the whole load..and wear til they break. So you have a slow and unrecognizable slow death of the BMS as when eg 5 fets are left it can only carry half the spec. For motor and propulsion you need a current free BMS ELECTRODACUSBMS is perfect but not available in 48V, so more or less contactor based ones like REC are your only correct choice. That just as a side note. I often use the combo in house that i have a main pack mostly from winston cell thats the master pack and eg starter and windlass is connected because this cells can do 8C peak together with an ElectrodacusBMS+BMV712, then parallel battery packs 1p4/8/16S with 280 or 304AH EVE cells+JK BMS+BMV712 to get the desired capacity. So they don't get any huge surge currents. the BMV712 then brings all the battery data into cerbo too.

I have to rethink my BMSes also, I am not going to take JK onto my boat. Same as you, I know these ones are probably OK, but I just can't trust them anymore.

​@@TheDigitalMermaid There aren't that many non-Chinese developed ones. I would look into a Batrium K9 and maybe still use an active balancer with it. I don't know why Andy has never at least showed support for a BMS developed in his own country.

@@davidb.5544 Because Batrium is not panacea either. They had plenty of firmware and hardware issues (and major changes to hardware without apparent benefits), and that at a much higher price point.

I'm in the clear, and I am sure my BMSes are as safe as they ever have been. The problem is that "as they ever have been" is a decidedly low bar. Really glad you're enjoying the videos, thanks for watching! ^_^

@@TheDigitalMermaid I wouldn't miss your progress (along with the inevitable trials) for the world.

BINGO. How the hell did they miss this flaw?!

They could at least make sure that the memory storing the value stays powered. It's a common functionality in any chip containing RTC functionality. But they could also use EEPROM or the internal program flash to store values (although over time that might kill the memory since they sometimes aren't made for many write cycles, depends on the controller) And most important don't ever run on unsafe defaults. If the settings are missing somehow, program it to either continue with safe defaults or just stop operating altogether and sound an alarm.

I was just going to say that! Having default values be very low, or even better... Have it default to an inoperational state if a memory loss issue or etc occurs, and only becoming operational after a user accesses the settings and configures it again. Its now 2024, there is NO excuse for nonvolatile memory issues, as you said, its programming 101. Most microcontrollers now have onboard flash storage. I always say programming and writing code is like art, and many do NOT have the touch. Same with GUIs. This is why I like to develop my own, because I know the firmware and all aspects inside and out. @@Ether_Void

I'm curious if they left NVM off as a cost saving measure, or just used a capacitor instead of a battery (again to save cost).

@@john_in_phoenix It's the internal Flash on the microcontroller, so there is nothing extra to add/no need for a supply. Apparently, previous firmware releases for this BMS didn't have the issue, so it's something that was introduced in the newer versions. Should be easy to fix with an update.

You're welcome. :)

Glad you avoided spending the money. Getting money back from JK seems as useful as squeezing a rock for blood...

Yeah that's the problem. An ocean and a national border standing between you and them. I came from the industrial control business. You make careless mistakes like that, people get fired and companies get sued. There's no recourse for these people. It just rolls off their backs like water off a duck. All the while you're left holding the bag.....

Welcome back! I know youtube can be brutal about deciding randomly not to send out notifications, even when you select all videos. I've gotten to the habit of always clicking on the "subscriptions" tab because I don't trust YT. Haha.

I wish I had another to recommend to you... I don't know what is a good budget BMS now.

I spoke to that in the video. My frustration is that this is a continuation in a trend of sloppy and hap-hazard approach to product dev. This is a safety device, and they clearly do the very minimal testing and QA.

@@TheDigitalMermaid I declined to watch the rest of your video as you were spreading false information in the first 10 seconds.

@@cgutowski471 Do you have evidence that it's false information? The idea that Andy would be wrong about this is quite the statement to make...

@@cgutowski471She is very clear in the video that it doesn’t affect all of their products. But she goes over other issues that do impact other products and that demonstrate carelessness by the manufacturer. I think she makes some very good points. What specifically do you think is factually inaccurate?

@@TheDigitalMermaid you made a very broad statement vs being specific to the new BMS that has issues.

Given my use-case in marine, and I suspect a decent fraction of my viewers are also considering electric sailing, this approach is not acceptable. In a Tesla or other car, you can pull over and call for a tow. If you're off-shore, well, good luck! This is why _I_ can't recommend them anymore. If others decide it's worth the risk, well honestly, I get it. I understand the appeal. It's just gone too outside my comfort level.

@@TheDigitalMermaid Honestly, for such mission critical battery, I'd probably go with a pre-built battery like Pylontec or something... Exactly for the reason you've mentioned... But yiu will still have solar and sails when all else fails...

@@rklauco Pre-built batteries are too volumetrically inefficient. Even with bare cells, I'm so space constrained that I am looking everywhere to shave off a few mm here and there. Now, this isn't the case for many other boaters, and for them I absolutely agree with your pov.

@@TheDigitalMermaid Yeah, this aspect is true... The flexibility of open crlls is great.

That would drive me insane...

I hope so, too.

Ya, seems like it's only the new model. However, as I said in the video, this is not a new thing with them. They seem to slap together crap and throw out to clients with clearly minimal testing or due diligence.

That's also what I get from his video... Recently installed a regular 4-8S JK bms and this specific problem didn't occur (turned off for a week) Still, it is unreasonable to expect everyone to test every safety feature of every BMS, there needs to be some trust...

@@TheDigitalMermaid I have two of the newer style JK BMS because of Andy, they are the 7s-20s with the push button to start them, I have had zero issues with them, and they balance so much better than the previous BMS I have had

The specs for the batteries say to not charge over 3.65v, so this is the limit as far as I'm concerned. Above that might work to some degree? It's not worth the risk though... I've seen what happened to overcharged LFP batteries...

Best setting to use for LiFePO4 is 3.55v and best setting for Lithium Ion is 4.15v I have been using those max limits for years with no issues.

I charge it to 3.54 v per cell

There's a video on KZfaq showing what happens if you overcharge just to 3.85V. The entire cell becomes seriously bloated.

If you charge to 4.2V you will have a bloated cell (and it will bloat well before getting to that voltage).

They don't, mine have been powered off for weeks without losing their configs. This is effecting the new BMSes.

Thanks. :)

Exactly, where the hell are the fail-safes in these things?!

Pinned comment, and I spoke to it in the video, this is not an isolated incident. This is just an egregious failure in a long line of bad design decisions, lack of QA, etc. Look at Andy having two different JK BMSes blowing FETs on over-current tests. Look at how they change, fundamentally, things like supported configurations or available ports under the same model number. As I said in another reply; this is the straw that broke the camel's back, not the whole bale.

There's not been many options to replace them. Even now, I'm not sure what I'll switch to. I've not hidden my frustrations at JK, this was just the last straw for me.

Exactly.

China QA is a bit like China amps, they are not the same as in the west... China is only interested in selling things and have no issues selling components that could be dangerous. China isn't the only country that uses its users as unpaid beta testers, Apple, Ubiquiti Microsoft etc have been doing it for years...

Aye, I think until there's a fix or replacement, making it a habit to immediately check the configs on power up is very wise.

Then your BMS is still on Firmware 14.03 - 14.10. These versions don't have this issue.

@@TheDigitalMermaid That same can and should be applied to anything amd everything manufactured with memory that can be lost or currupted not just this BMS, its foolhardy to think otherwise.

JK is the best of the "budget" brands still, if you really want the active balancing (I do), but I don't actively recommend them anymore. I don't have a better alternative, I suppose JBD I would consider safer, but then I don't know them well enough to say if that's actually true (the JKs being popular means they get a lot more scrutiny). I'm working on an alternative, but it'll be a lot more $$. =/

Victron's approach to their BMS and LFP setup is pretty unique, and only viable in their environment where _everything_ is talking to each other. They wanted to be able to handle the same kind of inrush currents like starting diesel engines, making them actually drop-in replacements for LA (LFA/AGM/etc). The problem with externally disconnecting charging in parallel battery installs, like I have, is that if one battery needs to stop charging, and turns off the charge from the Quattro/Multiplus/etc, then all batteries stop charging. If you have a contactor-based BMS, then the BMS can ask the specific battery's contactor to open, but contactors have their own trade-offs. There's no universal solution, but in the end you somehow must have something that can see the per-cell voltage and cut off charging/discharge reliably. I know some people run LFP without a BMS, and that's their choice, but it's not one I'd ever endorse.

O_O - holy sh!t

Holy shit, if that's true (and it would be in-line with my experiences with them), then they're making it even worse. None of their previous BMSes reset to default on reboot. The idea that they could make a change like that and hand-wave it as being normal is ... wow. Could I ask you to email me? Address is in the about page, with a copy of that response?

It's not the voltage, per se, but the heat generated above 3.2V. Basically, everything above 3.2v is just making the cell hot, not getting stored as usable charge. Don't believe me? Test it for yourself, cycle test 3.2 to 3.6 in 0.05v steps and see how much more power you get back out each step.

It's not "several months", it's "a few days". The idea that a restart of the BMS, regardless of the duration, could result in the damage or destruction of your cells is not a condition I would ever be comfortable with.

@@TheDigitalMermaid - The settings shouldn't change, that's for sure. I'm glad I've stuck with Overkill Solar and the JBD BMS's, thus far.

Thanks, and this is why I made the video. I know people may have chosen JK because I use them, and I would feel horrible if one of my viewers lost their batteries because of their BMSes.

This particular issue has been resolved, yes. I am happy for people who own this model. The general argument I made about JK's business practices stands though.

@TheDigitalMermaid agreed. I'm not advocating for the sorely lacking QA and customer treatment attitude either. Unless you are Andy or similar with their ear, it's a great big middle finger. I think the hard pill to swallow is this. They manufacture for their domestic market.

This specific issue is limited to the new inverter models, I believe.

I'm glad to hear you hadn't put it into production yet.

@@TheDigitalMermaidthanks to the whole youtubers community and the others that trying to help us all with all those alarming videos... !!!!! i have my tons of troubles with other brands so i wont judge yet this one ... didnt try any yet!!!! . you all keep the beat.

I'm sure my old ones are fine, too, but as I said it's more about recommending them. You just can't know what you'll get, even when you order a specific model number. That's madness to me.

For me, my biggest fear is that someone chooses to use JK for their build, because they saw me use it in my build, and the BMS they get damages their equipment. I would feel horrible. Even if JK changed completely their business and development practices, it would take a long time to regain trust, imo.

I hope so. In the meantime, if the BMS does reboot for any reason, be sure to check the config when you turn it back on.

@@TheDigitalMermaid Wonder if there is a way to setup an alert with Solar Assistant. Run it off a Raspberry Pi. I have so much work to do haven't gotten to that point .

When you're building a device SPECIFICALLY designed to protect your batteries and your equipment, something as simple as ensuring the settings survive being turned off is pretty damn basic. Also, where's the fail-safe? Why not make the default configuration one that sets the lowest max charge and the highest min discharge?

i toasted a 4 cell lipo and the ensuing fire from such a small battery was pretty scary.I DO NOT CHARGE THEM IN MY BASEMENT ANYMORE.

@@davidkettell6236 Li-po scares the hell out of me...

I'm guessing you didn't watch the whole video, I explained why my frustration goes beyond this single bug.

​@@TheDigitalMermaidYou should not be that frustrated. JiKong still builds the best BMS's imo. But...... another safety hazzard has been released. The "hacked" master password.

Interesting about the voltage range... it would help explain why the cell I had that dropped to 2.0v doesn't appear to be damaged. That said, the EVE specs say to maintain between 2.5 ~ 3.65v, so that's what I have to recommend others do of course. Interestingly, I've seen overcharged batteries that puffed up like marshmellows... I wonder now what voltage they actually hit.

​@@TheDigitalMermaid Yes, when LFP first hit the market, recommended charge and discharge voltages were very different. Many early "hardware" BMS (not programmable) used what would be very out of spec voltages today. The more reasonable voltages manufacturers spec today is the primary reason they are rated for so many cycles. Of course minor tweaks to chemistry are also a part.

@@TheDigitalMermaid I had a charger fail once and it took a few cells to a bit over 5.5 volts and they puffed up after being held at that voltage for several hours but surprisingly they never vented. It had to be close but LiFePO4 is surprisingly tolerant to abuse even when they vent it usually doesn't result in fire but we all try to keep the chances that a cell ever gets overcharged to a minimum where possible. When I noticed the cells I discharged them down to below 1v and discarded them the next time I brought cells for recycling. I definitely understand the need to follow the manufacturers recommendations and make the same recommendations. I too follow similar charging parameters to what Andy at offgrid garage is doing since it makes since to not abuse the cells any more than necessary.

5.5v!? Good lord...

The devil's lettuce gives me a vicious headache, I'll pass. I'm glad you've had good luck with your BMSes. Mine, the ones I got that actually worked, have kept working fine. I thought I explained pretty clearly in the video why I am upset, and it's not because of this one flaw. It's a long pattern of behaviour from JK that upsets me. If someone bought JK BMSes because they saw I use them, and they got unlucky and got a bad BMS and it destroyed their cells, I would feel horrible. I had to go on the record with my concerns.

I can understand the "build quick, break, iterate" model, but that has to be kept in-house. Anything sold to end users, particularly safety equipment, needs to be well tested. Clearly, the JKs are not. Writing a book would be a great idea, but the real problem there is just how damn fast things changed... By the time you got through the publishing process, it'd be out of date.

@@TheDigitalMermaid It's interesting that the JK "inverter" BMS version is now listed as "pre-order" only now even though they have already sold many and people have them! What are they going to do change hardware on the fly again to fix issues like they've done with the old JK BMSs? 🙃

@@davidb.5544 Almost certainly that's exactly what they'll do. If they screwed up working with Andy, I have to believe they Just. Don't. Care.

Those sound like Daly BMSes.

LOL, you are correct. Don't know what made me think I had JK's. @@TheDigitalMermaid

"at worst you overcharge a few cells" - which could destroy them. I'm going to do a follow-up video in the next day or two to address the idea that the charger can prevent damage, because I don't think that is a safe assumption. If you set you charge voltage to 57.6v, 3.6v/cell, and all your cells are perfectly balanced than sure, that would be fine. However, we know how incredibly flat the voltage curve is on LFP... If you had one cell above the others, and the average across 15 was still 3.3v, that's 49.5v, leaving 8.1v overhead for that 16th cell. If the BMS doesn't cut the charge, the cell will be destroyed in this scenario. This 4.2v flaw would easily lead to the destruction of a couple cells.

Andy deserves all the credit.

To be clear, there's a difference between actively promoting and showing what we use. I've never taken a sponsorship and I've pair retail prices for everything I've bought. I always explain why I chose what I chose, and I've often spoken to the issues about JK that annoy me (as I state in this video as well). As for proper testing, speaking for myself, my channel has never been a review channel, it's a channel to document my project and my process of learning. I've never claimed to be an expert .That all said, I know some people will choose JK because I used them, and that's exactly why I felt compelled to make this video.

MPPTs, chargers, etc can't see the internal voltages of the cells. I wrote this as a reply elsewhere, but consider a case where you decide you want to cut charging at 3.6v/cell, so you set your chargers to stop charging at 57.6v. If you have one high cell, given how flat the charge curve voltage is, you could have an average of 3.3v/cell for 15 of the cells, and the 16th would be allowed to climb all the way to 8.1v (15 x 3.3 = 49.5v). You need the BMS to be able to cut charging... More though, when combined with all the other problems I've had, and Andy has had, it's clear that JK just doesn't give a shit.

Another commentor quoted a reply from JK saying "well, just don't turn it off". If that's a genuine reply, and it would be in-line with how they've handled my complaints in the past, then no one is getting kicked in the butt. My core argument is the company culture over there... Sure, when you get the BMS with the features you expected and that variant performs as expected, it's good for the money. The problem is their willingness to change shit on the fly, without model number variation, and pass the buck to the end user for getting caught out. JK clearly does not give one damn about the users of their _safety_ devices.

Ooooh, I am very interested! I tried searching for 'SV Rover' but all I got was a lot of car videos. Can you tell me his KZfaq handle (@...)?

Not a Ytube channel. He does written blog with pics on thisratsailed.blogspot.com@@TheDigitalMermaid

I need more time to think, but at this point, that's currently the one I'm thinking of. I had the JBD Andy's got now, and I liked it, I only switched for the JK active balancing.

@@TheDigitalMermaid that's a point. I have external balancers and a voltage detection circuit to turn them on. Bit of wiring, but it works nice.

Absolutely

It only effects the latest BMSes, but it's yet another example of their corporate culture and product development ethos. Slap it together and throw it into production! The role of the BMS is too crucial to use the "build it fast and break things", at least not in safety products going out to customers.

that may be but i have never had a problem with a Daly BMS ,they be be old school but they work ok.

It’s not an issue even with the new ones. Because you simply don’t disconnect them and put them on a shelf after configuring them like Andy does. This is such a remote and unlikely scenario to come by for any user. The product is meant to put in a battery box, configure it and use it. Not take it apart and leave it disconnected and imagine you don’t need to set it up again when putting it in a new battery. I can guarantee you have to go change some settings no matter if you put it in a different battery box.

@@pederb82 The funny thing is that in his video, Andy says he hasn't had this experience. I think maybe on a community post he said he had been able to verify it. It was reported by a few of his subscribers. That said, when you configure parameters, the values should be written to (an) EEPROM, and they should be read back when the BMS first receives power. That's just good product development. The fact that this is happening says that they are either NOT writing config to EEPROM, or they're not reading it on power up. That's a simple mistake, but can cause some not so safe situations. That's just NOT good product development. It's a pretty fundamental part of the design. And yes, you should be able to take it out of one battery box and put it in another (your example) and have the setting retained. Of course, you MAY have to change some settings, if the new box isn't 'similar'

@@CollinBaillie let this be clear: I agree that it should be that way. It’s clearly an error. If I got my way an BMS would only work on a specific chemistry period. Nothing beats consumer proofing things. What I’m reacting to is the doom of using the product. I want to know more about what is going on in stead of just hearing it’s dangerous - coming from my component level experience when it comes to electronics. I don’t see the BMS loosing its volatile memory from simply turning it off, without disconnecting it from the cells. It just isn’t logical. IF it does - then we can bring out the warning signs.

Less about the BMS, as I put the fuse immediately after the main pack positive, but any T-Class fuse rated higher than your expected loads will work. Personally, I like (and accidentally tested) A LittleFuse JLLN-200.

Having your charger set to max out below the max voltage of the BMS is always wise. That said, external chargers have no view inside the batteries so they can't see imbalances in the cells. It's entirely possible that even if you the charger set to max 57.6v, if the cell average is 3.3v, and one cell goes high from imbalance, that's still 8.1v that can go into that one high cell. A BMS plays a cruicial role in safety, imo.

It JUST the Inverter Edition, NOT the previous versions....

What other so-far-undiscovered flaws are there out there? I just can't trust this company anymore. Now, I will still use the JK BMSes I have until I can find an alternative, but the shaky trust I had in the company and their products is gone now.

@@TheDigitalMermaid I'm only home a couple days a month so my JK is off almost always but so far it's not had an issue. I bet jk prices go way down now that Andy kinda blasted them . I'm glad he did tho for sure.

@@TheDigitalMermaid I wonder about Chinese electronics and if we were to go to war with them I wonder if they have some way of destroying our systems we've built with all the Chinese products lol

Did you watch the full video? I explained why I no longer recommend JK, and it goes well beyond this one flaw. This flaw was just the worst, and the last straw for me.

@@TheDigitalMermaid its only the new inverter bms not the others versions like we have. That flaw will also be fixed with a Rom adjustment.

This is just it; It's the culture of how they release products and how they (obviously don't) care about the customers. I'm glad this is fixed for people who own them, but that doesn't rehabilitate their reputation in my mind.

@@TheDigitalMermaid I am a software engineer also. I would never release a software patch or program change without a full unit test and QA cycle. I don't like "call back"

Do you have pictures or records of this? If so, would you mind sharing them with me? My email is under the About tab.

The problem is that the voltage curve is so flat, that it doesn't take much for one cell to spike it's voltage before the others. Unless the BMS can request the chargers to stop, I don't think it's safe to trust the chargers to save your cells. I think I'll do a follow-up video, because this has come up a lot.

Good memory, it was. I was lured in by the JK's 150A over the OKS's 100A and the 2A active balancer. The OKS / JBD BMS itself never gave me a hassle.

If I recall correctly, their supercaps they use to store the power during balancing are under-rated as well. I would need to crack a BMS open to confirm my memory, but ya. They're cheap for a reason...

This bug could destroy your batteries, full stop. No real risk of fire, but I wouldn't be surprised if it caused a cell to vent, and certainly swell.

If the defaults are hard-coded then a firmware update won't help, but an update could solve the problem. Another commentor mentioned it could be a bug that failed to write the new config to non-volatile memory, and if that's what it is, it can be fixed. However, a reset to defaults should always be a reset to fail-safe values, and this is not the case, clearly.

Σας ευχαριστώ πολύ ευγενικά, εκτιμώ πραγματικά την υποστήριξη! ^_^

I'm going to need some time to think about what I'll recommend, I've not paid close attention to the BMS world in the last year.

@@TheDigitalMermaid. maybe focus on the important things, voltage readout accuracy, SOC determination, accuracy, failure frequency, connection to your monitoring ..The Bms should be as simple and robust as possible for your boat ... waterproof could not hurt (although :-) the seplos is already running 2years on a racing boat in Bulgaria) ....less important , bluetooth, active balancer Ps.: you will know how to proceed, the second try will be a hit :-) all the best :-)

The MPPT, and any external charger, can't see the internal cell voltage. Say you set the charger to stop charging at (3.55 x 16 =) 56.8v, and 15 of the cells were at 3.3v average (3.3 x 15 =) 49.5v, leaving 7.3v for a single high cell to go up to. The issue with the BMS resetting the high voltage disconnect would still occur. If you've got something monitoring per-cell, well you have a BMS of some sort. :) I ordered the cells from QSO (Qishou) on Alibaba and had them shipped from China, took about 2.5~3 months iirc. Cheers, neighbour!

@@TheDigitalMermaid Thanks i look at the failure modes of a BMS, worst case would be a shorted Hexfet, it that happens your expensive battery's have no cell level protection. I always like belt and braces protection.

You noticed I said "his community"? Yes commented below also saying it was someone from his community that informed him. I'm not sure why you think we, who do this as a hobby and are not professional testing labs, should be able to be the first to find these faults is ... optimistic. Hell, JK didn't catch this first, which is the real thing that needs discussing. As for your take that Andy's opinions should not be trusted, well, between Andy's mountain of videos and knowledge, and the comment of someone random on youtube, I know who I trust more.

That's exactly what manufacturers use you reviewers for! Bata testers for their product! And you do get rewarded for it with free stuff and money from views off KZfaq. Prowse often commented on being used for that purpose! You sort of contradict yourself saying it is a hobby and you're not professionals than say for people to trust someone who really has only been doing this for three years. I know who Andy is, I have actually driven past he's place in my travels. Before all this he was a computer repair man. I'm just nobody and I'm not trying to be mean but i have been in the industry since 1998. You people are not making videos about baking cakes! What these channels are doing is serious stuff that has the potential to hurt someone who just follows along. You'll probably delete all this and that's fine.😁

@@cdonuts7335 My dude, do you have any idea how much we make compared to how many hours we invest? If I worked it out, I would be making way under minimum wage. We don't do this for the money. Only channels that get as big as Will Prowse make good money. Andy doesn't even have a Patreon, and the pay you get from KZfaq from ads is a pittance. I think your idea of how much we make is really way off. For most of us, this is a hobby... If I added up all the money I've made, from ads and patreon since I started the channel, I might have enough to cover the editing laptop and cameras I bought for this. I like to make the people who watch my videos happy, so normally if there's something I can do help someone feel better, I will. You want to feel the victim though, you want to feel like you're being silenced, right? I'm afraid I don't do that. The number of comments I've deleted since I started my channel is under 10. Also, saying you've driven past where Andy lives, as some sort of implication that you know him, is irrelevant and pretty creepy.

I didn't give you an idea of how much you or any others make I said you get paid and get free stuff. Yes Will has made big money but he's a very switch on guy who has numerous investments, he's very open about the money he makes and used to talk about it on he's live streams. The last is a bit of a word salad, good you want to make people happy, good you don't delete comments. If finding out who people really are is creepy? Ok but there are the ones putting themselves out there! Stay Charged 😂 Update 11 minutes after I messaged OGG explaining there maybe some liability and legal ramifications for he's video he has now posted a clip saying everything is all good now!! So everyone can relax and hopefully JK won't take the damage done too personally! 👍

Email the manufacturer. Almost certainly though it's not one of the new ones.

I did, it didn't work. It was a fairly narrow window where some BMSes were sold under that model number without 4S support.

@@TheDigitalMermaid Thank you for testing it, they really should held accountable, problem is they will only do something about it if it start hurting there business. SO the only thing we can do is not promote them and don't ever buy there products again. Real bummer tough i finally found something good.

It would have been so easy to say "of the chemistries we support, was is the highest low voltage that is safe, and what is the lowest high voltage that is safe?" and use those as the default cut-off voltages. It's such an obvious and simple thing to do, if they cared about the safety of their customers AT ALL.

@@TheDigitalMermaid Exactly. I cannot understand why the default is not "fail-SAFE". Plus, I agree with your point that documentation and specs are unacceptably opaque. With a company that screws-up that badly, I can safely say my next BMS will NOT be a JK. (Hey, doesn't "JK" stand for "joke" with these kids and their texts?).

JKs response would need to be 180 degrees different from how they normally react to problems if they want _any_ chance to recover trust, in my humble opinion.

I think the cost is more the issue that the country of origin... The trick is that China is good at making things cheap, but they can (like any country) make good products when the budget is there for it. I think this is a case of "you get what you pay for"...

No, there is a cultural difference. There's a common saying in China, "if you have the chance to cheat and you do't cheat, you're an idiot." Very different viewpoint. @@TheDigitalMermaid

@@TheDigitalMermaid that is true

If you can't return them, then fingers crossed they release a firmware to fix this. At the very least, make it a habit to check you settings any time the BMS is turned on after being powered off.

The problem is that JK changes features and capabilities without changing model numbers (hence why I had two BMSes that were 24v only). They add and remove ports on a BMS without changing the model number. This flaw could have been mitigated with fail-safe defaults, and prevented with even basic QA testing. Andy has had FETs blow at least twice because the JK BMS didn't cut the FETs fast enough in over current tests... It's clear to me now that JK can't be trusted, despite having some versions and releases that are OK overall.

@@TheDigitalMermaid ... Re Andy's FET blowouts w smoke on JK BMS. I remember seeing 300 second delay for an over amp limits cutoff trigger (possibly a ridiculous default setting? / vs my choosing a way safer 15 seconds for trigger timing, ... that is easily adjustable.

@@CaptBill69 The time to disconnect wasn't the problem, the timing of the FET shutdown was. There are many FETs in parallel carrying the load, if one shuts down slower than the others, then the load of the shut-down FETs starts to go through the last FET that is still up, overloading and popping it. It's poor /sloppy design.

See if you can cancel the order, or return it? There's a chance this bug can be fixed with a firmware update, so long as it's not a problem like having no non-volatile RAM on the system. The bigger problem in my mind is the proven track record of being careless, in all the senses of the word. I just don't trust them anymore.

I wish I had a good recommendation... I suppose in a pinch? The JBD (Overkill Solar) that I used early on in the build (I gave to Andy who did more testing on it). Do a good top-balance before you build the battery and you should be OK. Otherwise, consider adding an external active balancer. If you're building a 12v battery, there's a variant Andy experimented with a few months ago that is a rebadged JBD with direct support for an external balancer, that one looked good, though I've not played with it myself yet.

I would not hold my breath waiting for JK to do a safety recall. Most Chinese companies laugh at the thought of being sued. If it becomes a big issue, they will simply change the company name.

It frustrates me to no end that you're probably right.

I understand where you're coming from, but to me, "has a major safety issue IF you turn it off a while and back on" is ... well, huge. A BMS turning off happens, particularly if the battery is in a boat, RV, cottage or some other situation where you could be left alone for months.

@@TheDigitalMermaid Yeah, I wouldn’t use the new “inverter” bms especially in a boat. I absolutely don’t see any advantage to communicating batteries/inverter with a Victron and the black JK bms’s that you already have. You have bulk/absorb time and tail current adjustments so there’s really no need for closed loop. You already know the in’s and outs around the Victron+ JK’s (and what can go wrong). Even other high end bms’s have their issues, learning curve, a lot of money and a new place to mess up. Don’t throw the baby out with the bath water. Take your time.

@@SkypowerwithKarl Like I said, if this was a stand-alone issue, I'd agree with you. Problem is, it isn't. Their app is flaky, their FET timing is bad, they use questionable components, they fundamentally change features under the same part numbers... All of it together is more than "throwing the baby out with the bathwater". They clearing have poor QA and a healthy dose of just not giving a damn.

I have limited experience with OverKillSolar (JBD), and they seemed OK (though passive balancing). My experience is otherwise with JK, which I am not happy with. I don't have an alternative I can recommend yet.

@@MMMM2MMMM2MMMM this is what I was trying to get at with my video... It wasn't just the firmware issue, it was the sign that they do everything as minimally as possible.

Cheep BMSes combined with more energetic lithiums like NMC / Lipo is ... a risk. At least LFP is largely safe, save for the very most extreme abuse.

It was "the way" back then. If you look at the earliest videos I did with JK, I go into detail on it.

In my experience, no, the BMS charges out of the box. I've not specifically tested this, but I don't remember ever having to do it, either.

I mentioned in the video that I could forgive the occasional problem from a company. I'm a software developer and lord knows I've screwed up in my days. The problem here is that this isn't in isolation. On top of the various problems I've had with product consistency, app crashes, etc, Andy's has (twice I believe) blown FETs in JK BMSes in overcurrent tests. Clearly they build to minimum spec and throw products out into the market with little thought to safety or consistency.

​@@TheDigitalMermaid Yeah, my point is not to belittle your opinion, the problem is serious when it comes to cell safety. Im also do software development, im not sure is this BMS fault in software or in hardware area like memory gets reset when power is off too long. Never had app crashes or heard that any customer have fault BMS yet but like i said that we have not used any those new inventer models what Andy have, i need knock on wood right now :D Sun is finally starting to shine here in Finland, the solar panels are starting to produce something.

1. Safety devices, which a BMS is, has to be reliable when things unexpected happen. It would be lovely if we could trust a balanced bank to stay balanced throughout it's life, but that's not realistic. We have to trust the BMS to disconnect before a cell is overcharged, and this flaw, and the lack of fail-safes, doesn't provide that protection. 2. The vast, vast majority of people won't (and most can't) monitor their batteries as they reach full charge. Consider being under sail with solar and regen coming in, or driving an RV being charged by solar and an alternator... You have to focus on navigating/driving and trust the BMS is doing it's job. 3. The reason I am so upset isn't because of just this bug, though it's a massive failure in fail-safes and QA, but it's the last stray for me in a long series of problems, development choices, and corporate culture coming out of JK. I just don't trust them anymore. You can't even order a specific model number and be sure of what features or capabilities you'll get, that's madness.

@@TheDigitalMermaid Agree to point 3 for sure :). I also agree BMS is here to make sure all is well but on other hand if you looks at it from practical point of view. I understand and agree with what you said but at point BMS will shut down it doesn't matter what you are doing or what you are focusing on you have only two choises.. Leave it off and hope your system is robust so you don't have to worry even in this condition or continue even with alarm or what ever even if you know it might damage cells..you might be in situation where it doesn't matter if you depleet some cells more but you might need few watts to keep your gps phone or radio on no matter what.. That is why said BMS is needed but isn't critical ..because at that point it might not be important how badly cells are damaged but it might be live/death situation ..Ofc I would suggest one thing..there is BMS from JK it is that 1000A version that doesn't use real fets but relay ..so i would suggest to have one of those as well ..just to be sure If you want i can dig part number for that

@@TheDigitalMermaid B2A25SRP