The JK BMS with integrated active balancer. This is the one!

[@oneman29]

You have made sourcing and comprehending this topic so much easier. Hats off to you Good Sir! 🎩

[@creamshop]

Thank you So Much Andy for testing all these BMS's, making all the same mistakes we would have done and doing all the research , FREE for all of us to learn and enjoy, you are are the mother Theresa of the solar world, ok maybe not, Ghandy is better suited for you ! 😇🙏

[@OffGridGarageAustralia]

Thanks a lot Gilles! Appreciate your kind words.

[@duncans4489]

I bought the150A version based on your movie. It arrived quickly and your work made it really easy to set up. Thank you so much.

[@joselito7776]

It is through this invaluable video that I found out how to turn on the BMS without that dratted switch which has to be bought separately here in the Philippines. Thanks for this.

[@upnorthandpersonal]

I've been running two of those for the past year without issues. Probably the best BMS in this price range one can get.

[@mrzed6597]

You helped me start my unit a long time ago :) Still running without problems. Thanks ;) I fear the price of this unit will go up like a Falcon rocket now :)

[@upnorthandpersonal]

@@mrzed6597 NP :) I vaguely remember. I've done so several times for other people as well on the forum - at least there appears to be a manual in English floating around now. There should be enough vendors out there to prevent too much of a price hike. That said, with component shortages worldwide as they are, that might impact pricing as well.

[@mrzed6597]

@@upnorthandpersonal I fear it will be like the cells. A year ago EVE 280Ah was $1800. Now it is $2300 (for EU). More demand, higher prices.

[@Sanwizard1]

I agree with up North and Personal. I have two of these running now perfectly for quite some time.

[@Sanwizard1]

@@upnorthandpersonal is there a direct link to EVE?

[@offgrid2010]

Wow. You actually show all the features working instead of most posters assuming all the features work. Very much appreciated!

[@alwoolhouse6255]

Thank you Andy. I have finally received not one but two from China (the first one was lost then miraculously found). Just about to connect it all up and your videos have been a tremendous help. Cheers from Spain.

[@wideawaketotruth5301]

Would be unable to setup without Andy's help!

[@evil17]

I really like how the active balancer was still working 2A in one cell when you did some bms shutdown limit tests too. Good info n vid. I have Iphone, so I hope the App is as good as this one of urs. Thanks for all this great info Andy.

[@OffGridGarageAustralia]

Thanks Evan. I believe the app is the same for iOS and for Android.

[@microbiologycory10]

So this BMS is completely configurable through BY from iOS or Android…mo PC with Termite required?!? If so, take my money! Could you provide link to ENG user manual?

[@wideawaketotruth5301]

Supper Nice BMS! Couldn't setup without your help!

[@rocketfuel-]

After watching many videos of your chanel, i eventually decided to buy this BMS for my 80ah 7s li-ion battery that i've got from an electric stacker (the BMS was dead so they gave me the battery). Thank you for sharing your experience.

[@OffGridGarageAustralia]

Thanks. I've just installed this one permanently in my battery shelf. It works great.

[@markmorris6357]

Andy, I've learned more from your videos than from any other source. Carry on!

[@OffGridGarageAustralia]

Thanks a lot Mark!

[@upnorthandpersonal]

Power off voltage is the voltage at which the BMS itself turns off to prevent slowly draining the battery.

[@mrzed6597]

Funny side note: the very expensive LG RESU 10h does not have it (or set too low). A unit's battery was completely drained when it was 1,5+ years in a storage. Lithium batteries loose max 3% SoC/month.

[@OffGridGarageAustralia]

Ah, right.. that's a good tip, thank you. Makes perfectly sense. So turn off voltage will turn of the BMS once one cell hits this voltage?

[@upnorthandpersonal]

@@OffGridGarageAustralia Yes, exactly.

[@The2000redrocket]

Hi there I just got the new jk 200a with the display. It only has a red and black wire on the cable not hooked to anything. You connect these momentarily to start it. That was nice. The cable going to the display does not have the 12vdc power to power the display. I'm using alligator clamps across 4 cells to power it. And it is mostly in Chinese so I asked if you can change language somehow on it. It was 29 bucks. With the app I think it is not really a got to have item. The app wouldn't see the bms. So I had to go in my phone app settings and give it permissions. Then it worked. This is the 2a 24cell 200a I'm using on 8cell batteries so I had to get a 24 to 48v boost to power it. All in all I think this is a great device. I'm glad I got it. Nowi have to fully charge and draw it down to get the meter calibrated.

[@reversemyopia]

I can't thank you enough for making this useful video! My hesitation to build my own battery have been solved

[@OffGridGarageAustralia]

Thank you very much. Good luck with your battery build.

[@NounXXX]

​@@OffGridGarageAustralia📌 *Есть мысли, чтобы при отключении городского 220в, автоматически включалась JK BMS* ❓🤔 В Щитке стоит АВР

[@trevornelmes9331]

Just in case, like me, you have a BMS already and simply want the equivalent Active Balancer, JK also sell the same thing but as an active balancer only. If you already have your battery assembled and taped up, they also have an adapter board that you can plug your existing BMS wiring into from the battery, the adapter goes in to the active balancer, and has ports to cable to your old BMS.

[@OffGridGarageAustralia]

Ah, great information Trevor. Thank you. That's very good to know. Such an adapter makes a lot of sense.

[@davidswiggum]

So I bought one. Came 2 days ago. Installed no problems. Started with 6v battery. Worked fine. Balanced my battery on first charge cycle. Excellent product. No more Daly. Thanks for the video.

[@OffGridGarageAustralia]

Hey, that's great feedback. The internal balancer is amazing, right? I really like the functionality and ease of setup.

[@jcreedy20]

Hey bud, just curious, I'm looking at both the Daly and JK bms to replace my ANT BMS on my ebike due to the inadequate balancing force and the fact it is passive on the ANT. What is better about the JK over the Daly? I am looking to run 250 amp peaks. Nominal will probably be around 100 amps at cruise velocity. Will the 200a JK do 250 amp peaks??

[@brettwilliams6728]

I immediately bought one the other night after you posted this video. Just have shipping confirmation today. Thanks for the recommendation. I look forward to another video about what you learn about this.

[@OffGridGarageAustralia]

Coming soon. Don't be scared by the next video though 😌

[@jwsolarusa]

Please share the link with us

[@OffGridGarageAustralia]

@@jwsolarusa it's in the video description...

[@excillisbank2611]

Ce BMS est étonnant et incroyable ! je ne savais pas qu'il existait c'est vraiment un BMS HYBRID et très complet.

[@sergea1138]

Pas si complet, Il est bien mais il manque la gestion de la résistance de pré-chargement et impossible de gérer plusieurs bms sur la même interface rs485.

[@mrzed6597]

Also known as JK Heltec BMS. As we said half a year ago it is the best product for these cells. You did a big detour, but at the end everyone comes to the same conclusion :) There is a big thread about this BMS on Will's forum. With the description how to start it with 5V using a lab power supply. Also RS485 communication with RasPi.

[@CROSpunkie]

Do you know of any US resellers that stock these?

[@mrzed6597]

@@CROSpunkie Sorry, I am from EU. So I do not have a clue :) I ordered directly from China.

[@arhitektche]

link please

[@Cooldudeblue261]

Where is wills forum

[@OffGridGarageAustralia]

I knew about these BMS' for a long time already but I also wanted to explore other options, like the Daly and the QUCC with relay, the active balancers and smart balancers. All this all in one unit makes totally sense.

[@PRASTRO]

🎉🎉🎉🎉🎉🎉yesssss now you are in shape, I was waiting for this video since you started, I have 4 years working with this BMS and not a problem at all there are the best for your needs, congratulations 🎈🍾🎉🎊 you finally find the one 💪🏼💪🏼💪🏼💪🏼

[@charlesrichards5389]

4 years? Jeez, now I feel like I've been living under a rock.

[@OffGridGarageAustralia]

Thank you. They are on the market for quite a while. Good to hear they last a long time.

[@michaelperry2446]

Have u attempted the cascading feature to use 1 device for a 14s 7 p, configuration? multiple strings in parallel??? 1 device! i am having difficulty understanding the wiring schematic in the manual. Have been looking for a couple of years now; on youtube, and no one else has shown how they do it!!!!!

[@OffGridGarageAustralia]

No, I haven't done this. But a 14s1p is not different form a 14s7p form the BMS perspective. All parallel batteries are just one battery for the BMS.

[@FinnOlav]

Nice 👍 thanks for sharing.This video is 2 years old now, why are thwy still selling separate BMS and activ balancer ?

[@Nisse977]

Thanks for the video! I ordered this BMS after viewing your video a couple of years ago. My batteryproject has been delayed until now. So today I will start installing my JK BMS (JK-B2A24S15P). AND you helped alot so I will not get stuck with a BMS that would not start ;) Thanks to you I do now know the +5V start-trick :) My battery is a 20S33P li-ion battery that I have built for my electric moped.

[@jmaus2k]

What is really important with solar is that the charge current is as high as continuous discharge current. Great find.

[@OffGridGarageAustralia]

Both 200A for this one. Far more than I need.

[@tomtebloss89]

Had really hard to find a good BMS, i needed minimum 120a x3 and overkillsolars is only 100a. So I just ordered 3pcs 150A of this BMS to my first off-grid planning (even stocked in Poland :) . Thank you for reviewing different BMS! /Greetings from Sweden

[@GiocondoSticca]

Considering that 2 x 7awg cables have a maximum amperage of 30A x 2 = 60A how can it hold 200A in charge/discharge?

[@CHloras]

I have the same question. This is very strange for me. Does anyone ever tried to run this BMS ant max load? What is going on with the cables?

[@ahlidap]

I own a JK Smart BMS and I'm super happy with it so far... Highly configurable, no need for extra messy wires for balancing... I just think that, for big packs, they could allow fir up to 5A balancing and, of course, thicker cell wiring. Just hope they keep updating and supporting!

[@Refertech101]

As some one who does power systems and off road equipment I can tell you, all ways crimp and solder! then double wall heat shrink!

[@kyba74]

The only possible issue is that all mosfet based BMS, if they fail (IE due to high voltage spike from broken solar charge converter), will fail with a short. Thereby allowing full access into the battery. For that reason I'd be more inclined to use a BMS with a separate contactor

[@OffGridGarageAustralia]

Yeah, OK, fair enough. The BMS should be the safety device for the SCC. If the SCC fails, the BMS should turn off. So you mean we would need a third instance of safety. Something like SCC->BMS->contactor?

[@mrzed6597]

@@OffGridGarageAustralia There was a case on the forum where a 24V SCC got into short allowing the PV 100V 10A directly to Daly 24V BMS (FET's shorted too) and to the LFP cells. Cells bloating, magic smoke released. Since then we are searching for a cheap preventive solution to this possible battery killer error.

[@МаринаМишина-ц2р]

Dear Andy, for LiFePo4 this particular BMS (and as far as I can see all from this line) in fact CAN be used for 8S setup. LiFePo4 - from 8S, Li-Ion - like from 7S and LTO - yes, from 12S onwards). This is taken from specs page on Ali.

[@AlexanderBurgers]

It even works with even lesser cell counts but then you need to supply it with an external 12v supply to the B+ pin on the balance connector.

[@DanBurgaud]

27:07 "... the only i have not seen here is a pack overvoltage..." You are correct that to get to that pack overvoltage, it needs to reach cell overvoltage first. What I am interested is an overvoltage from the "source" wherein BMS disconnects itself from the SCC if incoming voltage is too high

[@Beyondreality76]

An important point for the JKBMS setup is the voltage calibration. Measure the voltage exactly at the battery connectors and set this voltage in the BMS-Setup. The BMS works well in total but the SOC finding is a mess. Why the did not make an entry to setup the SOC in the setup menue manually? Daly BMS has this option and it is more favourable to enter or correct SOC from time to time.

[@rudisoft]

Based on your review, I bought two of the JK-B2A20S20PHC (maybe I'm destroying one, yet better to have two than needing one). Thanks for your work!

[@MiguelSilva-mb6mb]

Yes, Finaly a great BMS - Just like mine. You will love this!!!

[@OffGridGarageAustralia]

I already do!

[@wizzie2k]

Of course we want more testing and we love the looong videos!! Keep it up Andy and don't forget to calibrate in between ;-)

[@OffGridGarageAustralia]

Thank you. I tried to keep the video shorted but it's just toooooo much to show 🍻

[@kondalaruthala3624]

Andy, Nice to see your channel. Very good

[@OffGridGarageAustralia]

Hey, thanks

[@Earlonics]

Hi Andy I've been using what looks like the same BMS (JK BMS) for over a year now, works a treat, the only pain is having to have 3 volts above battery voltage to switch the BMS on. Once its on it does stay on, the reason I got this one is for the 2A balancing, my other one was balancing too lower amperage.

[@OffGridGarageAustralia]

I'll have to figure something out in regards to the start voltage. It's not ideal having that but manageable. The BMS seems ideal as it combines a great BMS with an active balancer.

[@rocketentertainment7403]

Yup, im running into that issue consistently :( today, i just cant get either bms to turn on at all

[@bstaab2590]

@@OffGridGarageAustralia Was this topic followed up here! Or are there updates on the part of JK that enable switching on through another function?

[@OffGridGarageAustralia]

@@bstaab2590 That has been sorted with an upgrade on the BMS. It now comes with a start button and a display. I tested the 4S version with display here on the channel: kzbin.info/www/bejne/gnXEnaF5ZZaAkKc

[@microbiologycory10]

Is the new version with start button and display only available as 4S version (that’s the only link on website). If not, can you please provide link or part number for 12S+ with start button?

[@MikeMUC]

Hi Andi, which BMS is now the best you ever got hands on and tested for a 16S large capacity battery ? and which active balancer is the best you ever got hands on and tested for a 16s large capacity battery ? as there are 12A active balancers popping up on the stores now, did you also have a chance to test one of those ? Grüsse aus München (und ich denke ich darf dir auch Grüsse von Christian (der Kanal) ausrichten) 😜

[@stevenbraun3115]

I am using the LTT version of the QUUC. It has the black internal relay. The application is a 48V golf cart. I have LiNMC batteries in a 14s configuration with 135A. I also have 300W of roof top solar feeding a Victron 100 20 MPPT, a Victron BMV 712, and a built-in 15A battery charger. The BMS has been an absolute nightmare. I think it's defective. I cannot figure out how or when the relay works. I have ordered the JK BMS.

[@henvan8737]

It will be interesting to see if the RS485 port can be interfaced with the Victron products. Do the talk the same protocols.

[@OffGridGarageAustralia]

Yes, they do. Brad is working on this at the moment and I will announce it her on the channel if he gets this sorted. He's working on solutions for other equipment as well, DALY, QUCC BMS' and other than Victron gear.

[@skiguenny82]

Can you give it a try and a feedback if it works?

[@williamhustonrn6160]

Hey Andy, that BMS is very similar to the BMS on my electric bicycle setup. The resistance is really nice, because my bike battery is made from used 18650 cells, so I was able to learn about a high resistance and it protects the bank before it causes further damage. Also It needs start voltage to turn on also, but it turns on during the bulk charge cycle or in my case with the bank is low or dead, i am dumping as muck voltage as the 48v laptop charger can pump into it and because the charge voltage goes more than 5v over the bank voltage, it triggers it on.. and it starts doing its thing. The BMS on my bike turns off if you dont charge it after a few weeks, like something internally is ran off capacitor voltage or something.. but it turns on as soon as i plug it into the charger. The only time this bothers me is when the bank is 100% charged aand i have not charged or used the bike battery for a while, when i plug it into the bike, the BMS is not actively working at that point until i plug the charger into it again to charge it. Mine is like 30ish days it lasts before turns off..

[@OffGridGarageAustralia]

Thanks for sharing, William. Yeah, I wonder how I can do it when I have the battery in place. Not that the battery or BMS will turn off often but the occasional disconnect can happen and I don't want to connect a power supply all the time to trigger it again. Maybe the external e-bike charger is enough though... needs more testing...

[@williamhustonrn6160]

@@OffGridGarageAustralia if that bms is like my bike bms, as soon as solar starts to charge the battery it should trigger it during the bulking stage.

[@KoiAquaponics]

@@williamhustonrn6160 Hi, I received this BMS based on this video. So I have no clue about making batteries or connecting this stuff, and learning as I go along. My understanding is that I plug in the BMS and hook it up to the terminal where the charger terminal connects, when it's connected to the charger the extra voltage above 48v will activate the BMS? I also will be using my battery bank and this BMS in a DIY scooter. So I just need to make sure it works right. Thanks.

[@GREGGRCO]

No !! A real metal case ?! Crazy talk !😂 Our great grand children will have no idea what we're talking about ! My first good laugh of the day ! Thanks !!

[@OffGridGarageAustralia]

I know, it sounds, crazy, right?! 😂

[@hugodeandres1497]

Dont forget Daly BMS’s are widely used. It is all i can ask for to use in my 14s e-scooter. Its 12Ah and peak output of 18A. It doesnt need anything too fancy

[@danielardelian2]

From my understanding, when voltage drops below 2.6V, it turns off the discharging MOSFET, but it is possible to automatically recover by charging to 3.0 V. When voltage drops below 2.5V, the BMS shuts itself down to minimize battery drain. It will need the Vbat+5V power supply trick to restart.

[@OffGridGarageAustralia]

Does it shut down if one cell goes below 2.5V? Is that a feature? Have you tested that? I'm curious...

[@gregoryfierens001]

Andy - we all had to learn how to start this BMS I use a 2S pack of 18650 and connect positive to B- and just touch negative to P- (it takes less than 1 second).

[@OffGridGarageAustralia]

I have to figure out something elegant for that. Like a start button at the battery shelve ;)

[@gregoryfierens001]

@@OffGridGarageAustralia a small 2s pack with a press button on the positive should do the trick. I understand in the beginning you need it more than once, but as soon as the battery is up and running, how often will you switch off the BMS ?

[@timburk6097]

This seems to be the one! 8s available now also! Awesome! Thank you.

[@fionnhovawart9594]

8S, I can't find it on their site. BMS starts with 14S LFO..

[@renevandenberg2133]

Hi Andy, although this video is already 2 years old still very valuable. I'm currently setting up 2 48V batteries with these JK BMS's and found this video very helpfull. Thank you very much for this. But despite this I still have question left and that is regarding the size of endlug you mounted onto the black and blue cables. When I look at the diameter over the strings (5mm) the diameter of the lug should be more than 5mm. I would say 5.5mm which belongs to the size 16mm2 lugs. Do you agree on this? I would love to get your answer. Thank you for all the great work you are doing I learn a lot from your videos. Kind regards, René

[@holgerj7520]

The settings look similar to the ANT-BMS. Only the that one has no active balancer. Really good video

[@OffGridGarageAustralia]

Thank Holger. Never seen the Ant BMS or the app. I thought it uses the same xiaoxiang?

[@diysolaradventures7894]

Andy JK BMS have 4-8S versions of that same bms for around a $100 bucks on eBay I believe

[@GavinWallace18]

These Videos are FANTASTIC and made me start to design my own system. I have a question from Scotland though; Will the JK BMS work with the Multiplus 2 directly without a shunt? If so, how does the MP2 know the state of charge of the battery? Many thanks Gavin

[@OffGridGarageAustralia]

Thanks Gavin and welcome to the channel. Yes, you can just operate a battery, a BMS and the Multiplus II without a shunt. The Multiplus II will measure the battery voltage itself and disconnect if the battery is empty. No problem with that.

[@GavinWallace18]

@@OffGridGarageAustralia This is good! however we still would like to know whether it will display the battery charge percentage when connected to the raspi Venus OS using a mk3-USB interface? We are keen to know the State of Charge at all times. Thanks for your time 😀

[@GavinWallace18]

Any thoughts on the above Andy?

[@OffGridGarageAustralia]

@@GavinWallace18 I don't think it will display any SOC or battery state without a Victron battery monitor or shunt.

[@victorrizalfilosofi]

Just recieve the item today Thanks for the detail video Sir!

[@UKsystems]

One thing to know about active balancing that is often missed if it’s not done correctly it can cause extensive wear and damage to cells. I would stay away from it unless you know it’s done properly and purchase a separate unit

[@Josh-b3c]

Yeah I had a totally different brand and type too where you needed to use a multimeter on diode tester and connected across the b- and p- to get the BMS to turn on after you first connected the balance leads

[@charlesrichards5389]

I've seen some where you just short b- and p-, and others that have a separate trigger wire to touch 5v to turn them on. I suspect this one can be triggered on by doing what they said at 12:55 (touching 5v across b- and p- then connecting the battery) which would usually fry a BMS but this one seems to be made for it.

[@charlesrichards5389]

I noticed two more things: 1. At 4:34 you show that it has a Coulomb Counter! So, no more need for a shunt? 2. At 20:14 you show that you can enter the wire resistance for the sensor leads. DMI INC (in another thread) suggested that the resistance of wires (and terminals) could contribute to shunt "drift". If you're pushing 2A though long skinny sensor wires, I could see how that would be possible, and it's awesome that there's now a way to compensate for it!

[@OffGridGarageAustralia]

I have to see how good the shunt is. The Victron smart shunt integrates nicely with the Victron gear. To integrate this BMS, it needs a bit more tweaking. Brad is working on a solution...

[@basspig]

Mitechguy at Treeline power system says to hook a 9-volt battery momentarily between the B- and the black lead to turn on the b m s.

[@DMIINC2013]

Could you open it up and check the quality of cable connections to the BMS and what kind of cooling they have those MOSFET's? Thanks. I have older versions of active balancer and they work great.

[@OffGridGarageAustralia]

I will open it and check that. The cooling is not too important as the internal resistance of the FETs is only 0.3mOhm. At 200A, that's only 12W of heat generated.

[@DMIINC2013]

@@OffGridGarageAustralia True. However, one has to take into the account quality of solder job on those wires (which is wrong execution of how to attach wires to begin with) and fact that we are dealing with lowest cost china made FET's. Love the thinking behind this product and have been looking at these BMS/Balancers since last December but 7AWG wire and its attachment to the board has me bit worried. Looking forward to your next video. Thanks

[@upnorthandpersonal]

@@DMIINC2013 I wouldn't be surprised if this has Infineon or International Rectifier MOSFETS in it. Low RDSon MOSFETS are not that common, and even my low cost inverter had these in them. I remember opening the BMS as well, I just don't remember the FET they used...

[@glenb1356]

I just got my JK BMS with 1A active balancing. I charged the pack and the status display is great. The charging shut off like it should at 4.2V (NMC 140Ah pack). But, I have one cell at 3.65V. It seems to me that a 1 amp balancing capability is going to take a very long time to fix my half volt imbalance! ???

[@chevaliercognac8757]

Thank you for your very useful videos!

[@dave3005]

The B2A24S20P specifications now state that it will work from 8S-24S for Lifepo4 batteries.

[@OffGridGarageAustralia]

And it should also work for 4s/12V systems with a small booster installed. I'll test this soon...

[@dave3005]

@@OffGridGarageAustralia I just placed an order for this based on your tests. Should arrive sometime around the first week in November. Thanks!

[@arrongrist868]

I like the opening few seconds of the video, very funny. I think a lot of people will not get it unless they or their offspring have played the game. 😊

[@Infinion]

For this JK-BMS app, is there only one balance circuit at a time as indicated by the red and blue illuminated cell voltages? How many simultaneous balancing circuits does this active balancer have?

[@Iassonas65]

Hmm, 200 A Dauerlast mit zwei parallele AWG7 käbelchen am BMS.....Ob das gut geht? 🤔

[@CHloras]

I have the same question!!!

[@bonnetalexandre2085]

Hello 👋 Good video i wonder 1 thing, why don't you balance under 3.4 v ? Thank you sir

[@GreekSIMRACING]

I would like to see an actual test of this BMS connect to inverter RS 485/can bus with more than 2 same BMS.

[@OffGridGarageAustralia]

Yes, me too. Seems like I have to do this test at some stage with my the battery banks. But not connecting it to an inverter but the Victron system for monitoring purposes. Inverter connection makes makes no sense in my eyes...

[@supernovatiger8913]

Thank you man , i wonder if it provides historical consumption data ?!

[@Dutch_off_grid_homesteading]

Heya, oke oke that looks like a very good bms can't wait for the next vlog with testing this bms I still need 2 bms's

[@Deane14]

Hey, you said you can't use this BMS with 12/24v, Why can't I make a 12v 500ah pack with 20 cells using this BMS? Love your vids, very informative! Cheers

[@basspig]

I'm guessing that this is a bi-directional be Ms. In that there are separate charge and discharge on off selectors. If I turn on the discharge I get voltage at the output of the DMs I'm assuming if I turn on the charge that they will accept a charge from the solar panels. Anyway I think I'm going to like this PMS I have three of them and I have 3 16 cell 280 amp power banks that I'm wiring up right now.

[@bentleyjarrard885]

Thanks for the excellent all-in-one BMS review. I really like the Voltage Threshold setting so balancing only occurs during the charge cycle above the Set Point voltage. The only thing that worries me about this product is the 200A current being passed through the PCB, much prefer a separate high current contactor or relay like the QUCC product. Really hope they upgrade the firmware on the stand alone balancer products as well. I'm using the 2A version on a 120Ah battery and discovered the same thing you did, continuous balancing in the flat part of the cell voltage range tends to unbalance the cells. Perhaps a future video you could go into more detail about the CAN and RS485 communications.

[@OffGridGarageAustralia]

Thank you. Nothing I have tested so far was 100% perfect. The JK BMS though comes very very close and I would give it an over 90% rating so far. I'm not worried about the 200A for two reasons: I'm not going to push more than 100A through it anyway and the internal resistance of it with 0.3mOhm is so low, that even with 200A it causes only 12W of power loss. Heat stress is not a problem with this BMS.

[@typxxilps]

@@OffGridGarageAustralia the 0,3 mO is also a factor to take into account I had not recogniced or would not have realized. But 200A x 50V would mean 10.000W and 12W is not that big deal just 1,2 promille. My 1000 kWh battery usage needs 1200 kWh feed in to get 1000 kWh out, which would mean 0,0012 x 2.200 kWh = 2,64 kWh for the pure BMS and on top of cause a bit for the operation of the balancing part I guess.

[@legominimovieproductions]

I'm planning to buy the 200A/2A jk bms with rs485 for my battery pack, just waiting for a couple videos/reports on how they perform (are they really as perfect as they sound)

[@OffGridGarageAustralia]

Yes, the JK is very good. Most people use them these days for batteries from 4s-16s and beyond.

[@legominimovieproductions]

@@OffGridGarageAustralia I will buy 16 Eve 280Ah cells. I am just unsure about the whole Minus-disconnecting problem with victron, I already blew 2 cerbos because I managed to create a rare special condition

[@PowerPaulAu]

Looks really good. Ticks (almost) all the boxes for me, but I really wish they would also make some that are 4S and handle 250A, that's a sweet spot for some of the things I do. But for a home setup, it's ideal. Having so many settings is great, but for some people it may also be overwhelming, and it's sometimes a little too easy to make a mistake which causes problems. But hopefully it's pre-programmed with generic safe settings for the majority of people. Good find Andy, I'm sure one will be on my bench before too long. * Not sure about the main cables though, they look a bit small for 200A continuous!

[@OffGridGarageAustralia]

Thanks Paul. That's the big - on the list. It wont' work with packs below 15s configurations. The same with the active smart balancer I showed recently. 30V minimum voltage. I wonder if that is because of the active balancing and they need that voltage for the circuits somehow.

[@ytteman]

@@OffGridGarageAustralia It will work with 2-24 cells, but it needs a 40-100V supply on the B+ terminal, which can be generated by a DC/DC step-up converter. The B+ terminal is supply only, it can be different from the battery +. The current consumption for B+ is max 10 mA at 100V, so a very small step-up converter is needed.

[@SakCyb]

Yip I am also hoping for a 4s one

[@Danny-jh5kh]

Ive always used my multimeter in diode mode for starting jkbms :)

[@eduardoperez891]

Dear Andy. I'm ready to star my JK BMS, how could I find your instruction video for parameters settings and values. I will like to follow your instructions.

[@MrSeb-455]

Hi, one question. Do you think you can connect this JK BMS to the Victron GX device via CANBUS?

[@willgeorge5644]

I want to do a test like this on the BMS from a Nissan leaf, many available from scrapped battery backs. they are set up for li ion of course, but maybe that can be changed? I am interested in the operation principle. I think it may not be just a shunt one. I do have the circuit and there are some unexplained inductors and other components on each cell.

[@frankseidinger2112]

I liked the part where the Oettinger Pils is the solution of the day :-)

[@HaroldMcDermott]

I just ordered that same model, I've never put a pack together before infact I don't even have the cells ordered yet, but I'm getting 16 280ah eve cells, I've got 5600 watts of panels and 4 12v 200ah lifepo4 batteries in sires for 48 volts, so I'm gonna build this pack and wire to parallel to my batteries

[@HaroldMcDermott]

I'm in Canada about the same price but ca$

[@thetransducer6232]

Does using a BMS with active balancing negate the need for top balancing when building a new battery pack. Wouldn't the BMS top balance the cells when plugged into a charger?

[@billtackett7512]

Hey Andy- I bought 16 280 Ah cells and the BK BMS with 2A active balancer. I have a quick wiring question, hope you can help. For a 16S configuration Is it true that the number 16 pin, 24 pin, and B+ all go to cell #16's positive terminal? Or was this KZbinr confusing #24 wire and the B+ wire? I don't understand why #24 wire needs this. Seems #17 through #24 wires should all be removed from the connector. Just #16 and B+ wires should go to the last cell. Please clarify. Thank you.

[@deanrowles3665]

Hi again Andy, Have been googling but cant find anything. Do you by any chance know a link to a wiring diagram, having trouble working out the 2 black wires on each battery connection plug. Thanks

[@felaxchow207]

For the price point, it might seem to be a bit on the high side for the 200 amp version. However, if you price out the QUCC BMS with relay and the Neey 4 amp active balancer is about $20 USD more than Hankzor BMS with integrated active balancer in one package. For stationary power users, we're always dealing with the conundrum of incoming and outgoing electrons; managing both of them at the same time gets really interesting just following your real world experiences. EV users don't really have this problem since you're doing one or the other. The 200 amp continuous limit is workable for me and having multiple strings for redundancy is a good thing too. A FET based BMS with a programmable active balancer ticks all of the boxes for the application. Something to look into, I noticed that when you were testing the cell overvoltage condition. I saw that it stopped the incoming charge current and the outgoing too. It took a few rewinds of the video to catch it on the screenshot. I am not sure if it is a bug or not, curious to see if it is. We do want a way to drain down the overvoltage issue without causing a total blackout of the system. I am also curious about the RS485/CAN connections and what data can be extrapolate from them; this is especially useful in my case since I am solar AC coupled on the backup side of the inverter (all I can say, it gets quite interesting) to better manage my solar in offline mode. I can go with the Sol-Ark option at a cost of $$$, but its no fun if you can't build it and customize it to your needs. Keep plugging away and back to the drawing board for me on my battery setup design. Getting the bugs sorted out is always the project killer. :-P

[@upnorthandpersonal]

He didn't have discharge enabled at all. The BMS controls these independently. An over-voltage only disables the charge port. There are several drivers to read the data on e.g. a R-Pi, or in combination with Grafana etc. You can read out pretty much everything.

[@OffGridGarageAustralia]

Thank you Felax. I think I didn't have the discharge button on from the beginning as there was no load connected in this test. I checked again this morning and it certainly only turns off charging but leaves discharging on if an overvoltage situation occurs. Thanks for picking this up. And thanks Up North and Personal for elaborating on this already.

[@felaxchow207]

@@OffGridGarageAustralia that’s good to know, looking forward on the real world test while documenting your journey through the good and bad. While it is start of autumn here, the electrons will really be cooking in no time soon down under. Btw, you can use it on an 8s configuration by using a dc to dc converter to bring the voltage up to the minimum requirement to power it up. How efficient it will be is you won’t know till you try it.

[@GavinWallace18]

Andy, sorry but something you don’t tell us amateurs; what does the 24S mean in the BMS title?

[@OffGridGarageAustralia]

The BMS can be connected to up to 24 cells in series. A 12V battery consists of 4 cells 3.2V each. You put them in series and reach the 12V nominal voltage. That's a 4s system, 4 cells in series.

[@GavinWallace18]

@@OffGridGarageAustralia makes sense however I presume that the 24S means you can put any number of cells up to 24 but doesn’t have to be 24?

[@sreekumarUSA]

092521/1608h PST 🇺🇸 092621/0908h Brisbane 🇦🇺 Good day to you, Andy. Thanks much for exhibiting relentless quest for perfection. But for me, my CNS got hay wired and I’m in total confusion. Don’t worry, it’s my intelligence or the lack of it. I do really appreciate the mirth and the technology mixed together from Brisbane. Take care, Sir; please continue your quest, research and results for the public. Errr.. I saw a glimpse of Oettinger ! Have a nice weekend and 73s…

[@traviswansai2784]

The itching question concerning lifepo4 battery banks. What Balance current should really be required for a battery pack using brand new 100, or 200 amp hour batteries. And, What balance current, or cell voltage spread would be considered to be too much during charging/discharging that would indicate a bad cell. I looked at the EVE 105Ah specs yet no recommendations were found. Andy you have a great deal of experience in this area, so any recommendations would be helpful... Thanks.

[@juancazorla3746]

Hi Andy, are you sure a 2* 7AWG or 10-16mm wires can stand 200A charging or discharging continuously?, Would it be possible to replace those 2 wiring for 1*50mm or 2*35mm?, Victron is recommending thicker wires for that current than Chinese Manufacturers :S. Good video review btw :)

[@mandimandi2523]

Hi Juan! I did not use the short pieces. i replaced them by 2 times 16mm² equal to about 35mm² and continued after 15cm with the 35mm². i agree that the 200 A is very optimistic. 35mm² single cable can be charged with 160A according to german standards. I am also not sure whether the bms can withstand 200A/350A... and honestly i would not do .... i would limit the input/output to 150A... Compared to the DALY 200A BMS the JK is tiny ....

[@andreaswestling259]

Does JK have any of their new BMS supporting 4S setup? What would you recommend for a 4S Setup otherwise?

[@OffGridGarageAustralia]

No, the new inverter BMS is only 8s-16s. For 4s, go with the older JK-BMS. It's the best on the markt still.

[@korishan]

With the latest issues/resolutions of the JK BMS firmware, would you still recommend this unit?

[@stevemacdonald3522]

Happy Easter from Canada Andy. With the Easter theme do you worry you will have all your eggs in one basket with the huge BMS. Could you not have two half banks with a switch to transfer either one in the case of a problem with the other.

[@AlexanderHuzar]

Is there a device like this, but for two 12v batteries (24v system = 2x 12v)? Use cases: my UPS has two 12v 9AH SLA batteries in series and I'd like to balance them for longer life, passive balancing is ok. Use case #2 - I would like to balance the two 12V SLA series-connected batteries in a motorhome (24v system). I am aware of the Victron Energy battery balancer, but am looking for a much more economical solution. Just need a passive balancer that works when charging, not a BMS. SLA (sealed lead-acid) is what I'd like, but you can point me to an AGM too if there's a difference (pardon my ignorance).

[@kevangell-sale9090]

Hi Andy long time since we spoke it was last year when I first talked to you about a few thinks iam the Kev from uk I still watch your videos and keep passing information on via my facebook pages that I have. I just wanted to ask if anyone else had same issues with the new jk bms 4to 8 2amp Bluetooth version you did a video about 5 months ago I think. Any way I ordered 2 from a Amazon seller very good service with delivery but had problems with information I have just received and just found some information on but not a lot on this version also having difficulty in finding the software to update to the latest version as I had same problem as you did when you started to use. The jk bms web site doesn’t have anything re software updates on have tried doing online search for this update not a thing. I have email via my phone ad ther website won’t send emails at this moment have reconnected the seller but I think it’s an agent. Dot know if you can help with a version of This software as I can’t get anything to work at the moment. Lol. I wanted 4 weeks for the 2 to arrive it did exactly on the day that they started but can’t build my two 8s 3.2v 304ah units until I can get this software. I was interested to see if others had same issues What I can see is a good build. But at this moment in time had to stop the build so frustrating. Lol Anyway Andy keep up the good work on your project. I watch your videos In batches. Usually when I can’t do anything Ch. from Kev in the uk

[@danfitzpatrick4112]

JK has to be the best I've found! I have had the JK (balancer only) since the beginning of my setup and absolutely love it. (I use it for monitoring) and only balance at above 3.4v as a maintenance tool every now and then . This combo BMS/Balancer is the one I also will upgrade to at some point. Great Vid! Thanks for sharing

[@mihaitaiosub]

I also use two active balancers from JK. The problem with them is that it does not have the automatic start and stop function of the balancing depending on the cell voltage, at 3.5 volts for example. How do you start the manual balancing when you need it? leaving it on permanently could destabilize the cells.

[@danfitzpatrick4112]

@@mihaitaiosub Spot on. That is not available on the balancer only version. I leave the balancing off and only turn it on for the occasional maintenance. I wish it had the feature to turn on and off at certain levels in the settings.

[@mihaitaiosub]

@@danfitzpatrick4112 That's what I did until a day ago. Yesterday I made a small electronic change to the two devices that allows me to leave the balance on, without the device to do the balance in real time. I really trigger the balance with an external relay energized by the Victron charger depending on the total voltage of the battery bank, in my case I set it to 54.8 volts.Now it works perfectly. If you are interested in the change I can teach you.

[@OffGridGarageAustralia]

Thanks for sharing, Dan!

[@john_in_phoenix]

Looks like a Heltec BMS to me. Just FYI, most FET based BMS will let you turn charge and discharge on or off (including the Daly). Good video, not too long. You should try your four wire tester and measure the resistance for the balance wires. The best part is no extra wires for active balancers.

[@OffGridGarageAustralia]

Thanks John. I think these BMS' are sold under different brands but are all the same JK tech under the hood. I filmed a lot more and tested other functions but cut it out due to the longish video already. Well, there will be more following soon 😊

[@john_in_phoenix]

@@OffGridGarageAustralia Yes, I just called it a Heltec because that is what it was called when I first saw one reviewed about two years ago. @Up North and Personal has one, and yes, I think it is one of the best FET based BMS. I like relay based BMS, but you have to have two relays, so you don't disable discharging when it is full. Then there is the problem of finding a reliable relay that doesn't draw too much current.

[@SolvoltDkwebshop]

You talked well about these jk-bms and I bought 3 pcs. I ordered jk-b2a24210p and got sent version with rs485 plug in. I assembled them correctly with the balance wires which are all measured through. Put bms on negative. And put laboratory power supply with negative on bms-out wires and positive on battery plus, and with more than 5V difference, bms does not start. What am I missing in my understanding of how this works? Is there a difference between the versions of jk-bms?

[@jamesattwood6809]

Great Video Andy! Appreciate detail - and if a video runs long it means more detail, more learning and more knowledge shared. Just bought this BMS on your recommendation. I would really like to see a video on simplified starting procedure (using a 9v battery for example). I have visions of a tiny 9v battery just exploding with the wrong hook up lol!

[@gyulakun7346]

Hi Andy, I really like your videos, congratulations. I have a question, do you think the JK BMS with integrated active balancer can be configured for a lead acid forklift battery? 48V 775Ah. Between what values can the cell voltages be set? The main thing would be the monitoring, but if the active balancer also worked, that would be very good. I wish you good health from Hungary. Regards: Gyula

[@stelucostache5827]

Hello I watched your videos with BMS settings for 48v 280A batteries. I would like if you could tell me what the working voltages of the battery would be at a percentage of 20% and 80% respectively. Thank you

[@EdeksuperBob]

Hello I have a question for sure like every one here 😂 did u menage start the BMS and I try to find video if you do but no luck that's why I wrote here how to make start and keep that way so no need to connect any battery just get my Bms today and try to find out thank you for your answer

[@_layer8]

Hi Andy! Greetings from Germany! Can you tell me what USB interface you are using to connect the BMS to the Raspberry Pi?

[@OffGridGarageAustralia]

Hi Dominik, I haven't connected the BMS to my Pi yet. You can just us the Victron USB -> RS485 or Victron USB -> Ve.Direct cable. Have a look at Louis's project on Github: github.com/Louisvdw/dbus-serialbattery/wiki

[@_layer8]

@@OffGridGarageAustralia Thx Andy! Just made my order to "Dongguan Jiyuan E-Commerce Co., Ltd.". Ordered the 200A version with LCD and RS458 interface. Will post my experiences here.

[@rossallen738]

Has anyone here figured out a good way to jump start the JK BMS without an external power supply? I was hoping to avoid buying one since I only expect that it would be useful one time...

[@GerryMitchell-sg3dd]

I have watched many of your videos concern the BMS and active balancing. I am building a 230ah battery pack for a Polaris EV. I started with a Daly 500a BMS and it fried internally. I ordered another and it works but it doesn't read the cell voltage correctly which causes the charger to turn of prematurely. I have been in contact with Daly and they tell me it needs a firmware update. I cannot get my computer to communicate with the BMS. This is very frustrating and Daly is little to no help. I have wondered if adding an active balancer like NEEY could help with this problem. I'm really tired of wasting money with Daly. What BMS do you recommend to be the best all around?