The JK BMS connected to a 12V/4s battery. But there is a catch...

[@alsemi-back-up579]

If You Buy The 8JK S BMS There are NO P- ot B- Cables and NO Case. What a Rip Off for $176.00 Canadian + $35 Dollars Canadian Taxes. Great Video Andy .Thanks for Uploading No One Else Does Explain Like You Do !! Thumbs Up!!

[@OffGridGarageAustralia]

Thank you very much. The 8S has no case and no cables? First thing I hear about. Have you complained with the seller?

[@alsemi-back-up579]

@@OffGridGarageAustralia YES Hankzor They Said That is What They Sell I Told Then to give me a Refund. They Said When You Send it bac to Them ( Ali Express) you ALSO have to pay for shipping! From Canada to China not Worth TOO Expensive. Not very kind to me I Call it False Advertisement cause it shows on the page with case and cables! Very Upset!!

[@marc9063]

Nice now i can set my 8s 24v with the jk bms. Good job andy

[@OffGridGarageAustralia]

I probably would not do this with a booster if it is a working system. For that test is was OK, but how reliable is this over time? If the booster fails, the BMS won't work any more. Have a look at the other 8s BMS in the description. It has a 2A balancer as well and looks great.

[@ToThePointGarfield]

bought a b2A8S20P few weeks ago and it was a 24v 8s version. Didn't kick in on 4s. Seen your hack and indeed it works. Ordered a 12v to 24v converter now in stead of a new BMS with 4s capability. Tnx for all your insight, got a huge info out off it.

[@OffGridGarageAustralia]

Thank you for the feedback.

[@matthewknight5641]

Awesome that you did this video. I bought this bms for my 6s 24 volt 96 cell leaf battery pack. It's 24 modules with 4 cells per module. Thankyou

[@upnorthandpersonal]

I had around 1kWh today from my 10kW array - rainy Finnish autumn day :)

[@Zorlig]

You just need to 10x it :)

[@upnorthandpersonal]

@@Zorlig Nah :) Winter is coming - no matter how many panels, output will be zero.

[@menimbamatahari170]

@@upnorthandpersonal thermo electric generator may solved the problem..

[@upnorthandpersonal]

@@menimbamatahari170 Yeah, if only they were more readily available.

[@cowgerbry]

Thank you, Andy, great video (as usual)!!!! Just ordered the 8S version from the Minerals store.

[@OffGridGarageAustralia]

That'll be a good one!

[@Zorlig]

Your videos have gotten a lot better

[@OffGridGarageAustralia]

Oh, thank you very much.

[@mayterrace1971]

Hey, I just emailed JK today and they said they will have a 4s 12v active BMS out early 2022. Great can’t wait 👍 maybe u will test this one out as well 😂

[@MrWella1234]

Hello, greate information. Which store did you ask?

[@alexschulein7002]

Hi Andy Again a great video, keep it up!!!

[@OffGridGarageAustralia]

Thanks Alex!

[@andylambertz4364]

Thanks a lot! Will buy some merchs for sure!

[@OffGridGarageAustralia]

Thanks Andy. From Andy

[@paiusanwilhelm6639]

hello, you don t need any booster or so.. i m currently running a 7s without any boosters.. just connected the wires normally 1-7s and has no issues.. anw thank u so much for the videos!

[@angelobautista5]

Good to hear this. I've already ordered the B1A24S150P variant and my setup is 8s lifepo4. Based on their datasheet, it's supposed to work for 8-24s.. fingers crossed

[@theoteam4641]

At 18:44 you said that Stephen has sent you a link to the 8S BMS from JK, with that can i just connect it to in a 4S configuration and it would just work?

[@OffGridGarageAustralia]

JK just upgraded their BMS to make it work with 8s-24s configuration (it worked with 10s-24s before). For a 4s setup, you still need a booster for the power supply of the BMS unfortunately...

[@theoteam4641]

@@OffGridGarageAustralia thank you for that. I’ll be doing 8S congratulation after all as it would be easier to be on 24V than on 12V lol

[@theoteam4641]

@@OffGridGarageAustralia are you also able to build a battery bank with the jk bms showing how to add Can bus or RS485 dongle to it?

[@dave3005]

Awesome, I just ordered one of these.

[@OffGridGarageAustralia]

Great, I really like this BMS.

[@firpofutbol]

I thought you said Sunny Heart, Australia thinking this is where what you said you were filming from. I did Google maps search, then Google corrected it to Sunny Hart. And boy the results that came up Lol xxx. Never found Sunny Heart on the map.

[@offgridwithpojectham]

Andy, where did you purchase your Noark Circuit Breakers? I have not seen you post this information. Maybe I missed it?

[@OffGridGarageAustralia]

I bought them locally here in Australia. There should be a link in the description when I did the video about the breakers a while back. www.tro-pacific.com/products/100a-2p-dc-mccb-9md1b-tm-noark

[@bigbeef2654]

so what happens if the boost converter loses power/dies? will the BMS just turn off?

[@DavidHalko]

That seems to be the case, a nice test to run!

[@OffGridGarageAustralia]

Yes, that's a big concern for such a setup. I forgot to mention that. It's a high risk. I'm not expecting that anyone is really building such a system as it would consume 2.4Ah/day just for the BMS...

[@PowerPaulAu]

That's actually a really cool little "hack" to make these BMS's work on a lower voltage! Looks like I'll be going clothes shopping soon too :)

[@OffGridGarageAustralia]

Hahaha, you make t-shirts with your own stuff 😁

[@whatwhatdidtheysay...lyric2373]

Thanks so much for doing this!!!

[@OffGridGarageAustralia]

Thank you!

[@jasondevine6014]

Great video on the workaround. The BMS probably doesn't need such a big boost converter, a smaller one would have smaller idle current.

[@OffGridGarageAustralia]

That's pretty much the smallest I could find which covers 12V and also 24V input.

[@mannyfragoza9652]

nice job Andy

[@OffGridGarageAustralia]

Thank you.

[@excillisbank2611]

Très belle expérience je suis surpris de l'approche technique ! merci

[@wayne8113]

Thanks Andy

[@OffGridGarageAustralia]

Any time!

[@ochjoo77]

Did you ever test what kind of current draw the actual BMS has? I couldnt really findn any info on that on their website.

[@OffGridGarageAustralia]

It did test this in one of my videos. It was like 0.1A when the relay kicks in but then lowers to around 30-40mA to hold the relay at this state. It has an 'economizer' which lowers the amps.

[@meganote]

Interesting work-around, but I think I’ll just hold out for the 4S version or stay with my simple Daly (non smart BMS) setup. Thanks for the info!

[@OffGridGarageAustralia]

Yes, I would not put this into a production system. This was just a test to see how and if it works.

[@martehoudesheldt5885]

now i know where my daylight hours went to. enjoy them. WA, USA

[@cancan1970]

J'ai une question technique. J'ai fabriqué 4 batteries de 304A LIFEPO4 et j'utilise le JK BMS B2A8S20P-HC. Ma question est-il possible de mettre 2 de mes batteries en série pour obtenir du 24V sans endommager mes batteries et mes BMS. Merci beaucoup de votre collaborations Chris

[@kirkoliver2878]

You are incorrect that the negative in put and output are shorted on the board. There s a ~0.47 ohm resistor between them to sample the output current to sample the current for the adjustable current limiter. The secondary load should have an isolated negative if you want the current limiter to work.

[@OffGridGarageAustralia]

Thanks for your comment. I checked the board and could not see one. But there is SMD soldered as well, so could be....

[@sebastienl2140]

I fry some cheap dcdc converter because of that, so bad current regulation isn't on input gnd side or on output positive side (more expensive)

[@TheMrmalbec12]

Good video, makes me see what else I can do, and thanks for the comment of another subscriber 👍

[@OffGridGarageAustralia]

Thanks Fred!

[@dison4linux]

Great Video. Do you know how to read the data from the JK-BMS over RS-485 or CANBUS? I'm interested in getting the BMS data in Grafana/etc but I haven't come across any guides on how to do that. Jon

[@upnorthandpersonal]

I've tried to reply to your post, but seems certain words get the message removed automatically... Check Will's forum. Some of us are using it over RS-485 with Grafana.

[@OffGridGarageAustralia]

Can't find a reply from you in the filter.... links or naughty words are been filtered automatically 😉

[@upnorthandpersonal]

@@OffGridGarageAustralia Nothing like that - just a combination of words describing a certain site we all know. I'm not the only one who noticed this...

[@OffGridGarageAustralia]

@@upnorthandpersonal As soon as there is word.word like this, it filters it. Nothing I can do about it. That's what KZbin does as it thinks it's a link.

[@upnorthandpersonal]

@@OffGridGarageAustralia I know - I didn't use that at all. I'll make sure I copy my next comments and if it happens again I'll email it to you.

[@todamnbad]

Will this work on the neey? Also instead of using a 12 to 24 volt converter could I use a power supply from an old plug in device, I have an old calculator that uses a 24 volt plug

[@OffGridGarageAustralia]

Yes, that will also work with the Neey balancer. Same principle.

[@ladbla1752]

Thanks for the video. Can you please let me know what is P- cable used for? I mean in real working?

[@johnjansen1002]

Are they making this bms for 8s configuration without a buck boost. Hope they have come out with one recently

[@marioegal9156]

Moin Andy, wie heißen denn die kleinen Stecker für die RS485 Schnittstelle? Die sind leider nicht im Lieferumfang 🤷🏼‍♂️

[@theoteam4641]

How about using the jk 8s Bms? Would i just set the boost at 24v?

[@OffGridGarageAustralia]

The booster can be set from ~28V-55Vto supply power to the BMS. This is the voltage range the BMS needs to operate.

[@stevenfrazier8939]

My JK-BMS came without lugs. it says 7 awg but I can't find a lug to fit, any ideas?

[@stevenfrazier8939]

what size crimp ring for the balance leads?

[@reneroman1421]

Hello... How can I synchronize the BMS JK so that it gives me the most accurate load% readings?

[@kimsandb]

It seems the JK BMS now also has a 8s model to select from your link.

[@OffGridGarageAustralia]

Oh, yes, they do! I should change my website, ey? Thanks for letting me know.

[@reneroman1421]

Hello.... Is canbus communication compatible with Schneider inverter ??

[@jackoneil3933]

Thanks Andy! Excellent walk-through, and I was wondering for those who may not have an adjustable bench power supply if It's possible to use the JK BMS in a 1S configuration to provide over-voltage protection for top balancing?

[@OffGridGarageAustralia]

Thanks Jack. A 1s setup should work as well with the same booster.

[@sebastienl2140]

No you can't set 1S only 2s but easy to put fake cell at 5V with 3A USB charger

[@OffGridGarageAustralia]

@@sebastienl2140 why can't you set up just one cell?

[@jackoneil3933]

@@sebastienl2140 Thanks, Good hack. I suppose top balancing a couple of strings would be good enough as well.

[@Mr.X3D]

If JK had a booster built-in they would own the market.

[@OffGridGarageAustralia]

Yes, that what I was thinking too. If they would just integrate one...

[@Mr.X3D]

@@OffGridGarageAustralia Can you check what voltage is required for the BMS to start? For instance the NEEEEEEY 4A balancer actually works from 25v according to HankzorBMS store. The spec states 30v but when I asked them what boost converter to use in a 8s setup they said it starts at 25v, hence I would be ok for top balancing. Reason I ask is that there’s tons of small boasters that boost from 3,5-30 up to 35v.

[@5UPRAH]

How much current is pulled from the 48V step up/boost converter? Looking at doing something similar but there are a few options and want to make sure it doesn't draw too much from that B+ side through the lower output step up/boost converters....

[@OffGridGarageAustralia]

I've shown this in the video. It was 30mA from the PS and a bit less when using this other booster (link on the homepage).

[@scloh1]

Andy, I just looked in the store but I couldn't see any OGG s̶t̶u̶b̶b̶i̶e̶ SPAT holders! These would be useful for thermally isolating your hand during calibration. :D

[@OffGridGarageAustralia]

Coming soon... 🍻 Absolutely necessary PPE

[@pauld5530]

Any updates on JK releasing a 200a 4S BMS?

[@geoff8746]

I have the JK 8S 200 AMP version, just configured as Andy suggested, is working great is a 4S configuration. I'm going to order another one from Ali Express. Same App as the 24S model, no case, no attached cables, however it does have 2 x M6 threaded bases on B- and P- which worked out great. I just made my own cables the length I needed them.

[@OffGridGarageAustralia]

It's there, just arrived last Friday. Review and comprehensive test is coming soon. It's not in the shops yet though...

[@simonflensborg8109]

Hi Andy the JK BMS is it possible to Discharge the battery to let us say use it to charge car ore the home !!!! and also charge it at the same time from grid ore sollar ore will it confuse the BMS ! can it handle both things at the same time ? Regards Simon DK

[@OffGridGarageAustralia]

Simon, the BMS is there to protect the battery as it monitors single cells and cuts the power for charging or discharging if something goes out of control. It's not responsible for charging. Everything you want to do has nothing to do with the BMS.

[@simonflensborg8109]

@@OffGridGarageAustralia but why Andy why not use a BMS to control both you now !!! 🤯 My brain...... A BMS whit a separate com port there you charge and discharge at same time rite why not use somthing like that to control both at the same time. Now i am confused danish man confused Andy 🥴... In and active powerwal there Wil always be current goin in from solar ore source - and out goin to the house ore car ore other toys 😆🤙... But why not use a BMS whit seperater com port to control both same time ??????? Uhhhh my head 🤯🤣🤌😂... Thanks for taking time to read the post very cool 🏄🤙....

[@OffGridGarageAustralia]

@@simonflensborg8109 now MY head hurts...😁

[@simonflensborg8109]

@@OffGridGarageAustralia yes ej ej 🤣🤌... Just like in in Tesla when you drive you consume energy and break you generate power that most be Discharge charge BMS in some way... Hope your begining to flow me... And i am not saying it is the only way to charge the cells but activt i shut work both ways.... Sorry my translation is so bad the stupid phone wants to write in danish All the time 🙄🤣 regards from Denmark 🍻🍺🍭

[@Sylvan_dB]

Are you familiar with "blu-tak"? It is a moderately sticky putty often used to temporarily attach something like a paper sign to a wall, allowing it to be removed without a trace. There are many brands. A blob of blu-tak is a handy bench tool to hold things like the balance connector while you measure the voltage on each terminal.

[@OffGridGarageAustralia]

Yes, have this stuff down here as well. Good tip, thanks.

[@TrevorFraserAU]

Nice!

[@OffGridGarageAustralia]

Thanks!

[@venkateshagopalgopal4532]

Upto 7s pack, Skyrc professional charger will do balancing ! Why risking BMS/Boosters?

[@OffGridGarageAustralia]

For testing purposes, to show it is working. I would not recommend this setup for production systems. All info is in the desription.

[@matthewknight5641]

Andy please tell me an app that I can download to my phone for the jk bms. When I try jikong bms it says not compatible with my phone. Please help with this

[@OffGridGarageAustralia]

Your phone might be too old? The link to the JK BMS is on my website: off-grid-garage.com/battery-management-systems-bms/

[@matthewknight5641]

@@OffGridGarageAustralia my phone is about 2 years old so you are probably right. Thanks Andy. I watch your stuff everyday while driving this semi truck and you teach me alot. Thanks

[@OffGridGarageAustralia]

@@matthewknight5641 I have the JK software running on my 10 year old Google Nexus 7 tablet, so can't be the age. I'll link an alternative software on my website tonight, which you can try. off-grid-garage.com/battery-management-systems-bms/

[@JeremyAkersInAustin]

My Orion Jr2 runs just fine on 12v with no booster needed. 😛 It actually has two separate power inputs. Which is handy because I can power the BMS from the 48v battery itself or from my RV 12v system. So if my 48v battery ever drained down so low that the BMS shut down to protect it, I can power the BMS from the 12v system to get the BMS running so that it can allow charge to occur.

[@OffGridGarageAustralia]

The Orion... again... 😊

[@JeremyAkersInAustin]

@@OffGridGarageAustralia Haha I know... But it really is a pretty good BMS and it's made in the USA. 😁 And if you have any issues at all you can pick up the phone and call them or email them and they are really helpful.

[@SuperRockmonkey]

I think I need to retract my comments about you buying a Batrium Andy. I’m loving how well this BMS seems to work! Question regarding balancing though. When it is balancing at say 2 amps, is that total balancing current (sum balancing current of all cells that are being balanced? Or is it balancing at 2 amps per channel/ cell. Ie if 2 cells are balancing it’s actually balancing at 4 amps?

[@kenl6880]

The BMS really only balances at half the rate it says. It only works on one cell at a time. It will discharge one high cell at the rate set, into a built in capacitor, then charge a low cell with that capacitor at the rate set. It only does one at a time so while the actual current is what is set, its either charging a cell or discharging a cell at any given time. It's not doing both simultaneously. On average, the balance rate is half of the value set because half the time is discharging and the other is charging.

[@SuperRockmonkey]

@@kenl6880 Thank you, very helpful. Do you have any experience interfacing the JKBMS with Victron equipment vis Canbus / RS485?

[@kenl6880]

@@SuperRockmonkeySorry, I don't.

[@OffGridGarageAustralia]

Thanks Ken. That is correct. The balancer discharges one cell with 2A and charges a capacitor. Once this is full, it discharges it with 2A to another cell.

[@sebastienl2140]

Bms take 2A from one cell to supercap THEN discharge this supercap to one another weak cell, so real effective current is 1A from cell 2 cell

[@bonhardtlaszlo6311]

did you try it without boost converter? I have the same BMS like yours on the backside it says 13S-24S, i ordered my BMS when the description at hankzor store said 13S-> 1 week later they changed the description to 8S->, tried my BMS and it turns on fine with 8S battery... without any "hack"

[@bonhardtlaszlo6311]

actually i did more testing and it seems not stable with 8S sometimes the BMS turns off:/ , but i ordered a new one which supposedly have some internal stuff changed that can handle 8S natively

[@anthonycraig274]

This is great but is it worth it? Wouldn’t it be better to use a good quality 4S 12V BMS like OverKill Solar 120A

[@OffGridGarageAustralia]

Yes, absolutely, this was just for testing purposes. I would not recommend using this in a production set up.

[@wideawaketotruth5301]

Andy, so I have eight batteries that are 3.2 304ah if I run those in series to create 24 volts could I use the booster converting to 48 volts and then convert the 48 volts to a 220 plug for a mini split air conditioner heater? Thank you.

[@ascii892]

The boost converter is only capable of a couple amps, so that would not work. You should use a 24 volt inverter.

[@jounik]

Would it not make more sense to run the inverter off the 24V directly without first converting to 48V?

[@wideawaketotruth5301]

@@ascii892 so with the 24 volt inverter you're saying I would be able to produce a 220 plug in for my HVAC?

[@wideawaketotruth5301]

My primary objective is to be able to create a 220 volt plug in for my HVAC. Clearly I do not understand how that is going to work. Could you please elaborate on how I would need to do it if it's possible?

[@ascii892]

@@wideawaketotruth5301 you can get an inverter that has a 24 volt DC input and a 220 volt AC output.

[@ImanAcademySE]

Andy great video Please verify this issue , I have 48 v connected to a charger and I set in jk bms max charge to 6.12 while charger in on and balance is on it try’s to balance all cells, 6 of them are still under 5.5 but this is not the problem if I disable balance and charge and discharge in jk bms all cells go down to 5.35 and you can see the balance working although I disabled it The battery is not connected to anything but a charger I am not sure why it does not keep same charge

[@jws3925]

Yes, you made it work.........sort of. Is this BMS really that good to do this work around? I don't think so. Besides, it appears that the manufacturer may just come out with a 12-24v model. I would not go to all this trouble for this BMS. Great you were able to do this work around but for me I will either use a BMS made for 4-8s or wait for JK to come out with one. I am not sure BK is my choice even if they do.

[@OffGridGarageAustralia]

Yes, I agree, John. I would not do it either. It was in the manual and looked interesting.

[@sebastienl2140]

Plus you can't start the bms with a charger (normal starting method) or without a breaker to isolate the battery before sending 18V on a DC bus with devices normaly happy in 12-14V range. Personnaly i use a mppt boost converter because it's shutdown the 40V needed by this bms in case of lfp deep discharge < 12V (mppt setting)

[@AlexTorres-qv3hv]

Hi...nice work!!....Have you ever tested the overvoltage cut out threshold of the bms while charging with those mppt CC? ....check if after the bms disconnect them from the battery they ride at the pv VOC...if that's the case this high VOC could damage the bms (depending on its VOC threshold) at reconnect point...im posting this since there's a video of a bms that went berserk after going thru this situation letting the over voltage pass to the batteries causing a wreck havoc...🤔

[@yanziqiang]

Do u think it's possible to use the correct 8s version, 2 of them , on a 16s pack, so as to have 2x 2A balancing channels so to speak? I hv drawn the schematics n feel it could really work. Just would like to get confirmation from you or your experienced friends if this will work. Tq. Always a joy to watch your tech videos. Cheers.

[@OffGridGarageAustralia]

So you have a 16s battery with but want to use two 8s BMS for it?

[@ennyw20]

Nabend... Spannende sache auf die Idee bin ich noch garnicht gekommen.... 🤔 Haben sich die öttis endlich bei dir gemeldet? Ps hab mir mal ne Tasse bestellt 🤣🤣🤣🤣🤣so geil

[@OffGridGarageAustralia]

Die Dosenfirma hat sich nicht gemeldet, nein. Danke fuer die Tasse, habe gesehen, das eine nach D geht...

[@ennyw20]

@@OffGridGarageAustralia das gibt es doch nicht... Werde gleich nochmal ne Mail schicken... 🙄 Ich dachte das ist längst in Sack und Tüten... Na hoffentlich ist die Tasse schneller wie das das zeug aus China 🤣🤣🤣

[@dig1035]

Thumbs up and subscribed! Why JK BMS? What's so different than other Chinese BMS, please respectfully? Interesting, running a 14+ cell BMS on 4 cells! Does JK make a 4s?

[@OffGridGarageAustralia]

It has an active 2A balancer included. They don't make a 4s BMS with active balancer, no...

[@igorkvachun3572]

Yes 👍 🔌 🔋 ⚡ 💡

[@HeinzMeulke]

The true test of a BMS is if it fails when you run it at the max rated capacity, if it is rated at 100A then put a 105-110A load on it an see if it lets out the magic smoke. I would love to see the JK Bms doing real work other than balancing the battery. The abuse test is a good indicator if people will be able to use a BMS for charging/discharging in the real world

[@chrishartley1210]

Do not assume that the negative connections are directly linked, it isn't always the case. If there is any current control on the device then there is almost certainly a current sense resistor between the input and output negative connections. It will probably be only 0.1 ohm so most multimeters will not detect it. Check visually. The input negative will be connected directly to the ground plane. It the output negative is not also connected directly to the ground plane then you have a current sense resistor so you need to connect both input and output negatives. On the other hand, if both input and output negatives are connected externally then you will have problems with current control.

[@OffGridGarageAustralia]

That's why I made the test with the ringer. It works in both directions, so...

[@diydsolar]

@@OffGridGarageAustralia i think he is saying that you need to inspect visually the board. Usually they ring even with 1 or 2 ohms, so you can't detect shunt resistors with "ringing"

[@todamnbad]

Really wish I could follow your instructions better, been working with my neey and an external power supply and I get nothing, I can power up the neey amd open the app but I show no voltage or anything for the cells

[@OffGridGarageAustralia]

Did you check the balance leads that they have the voltages in the right order. Do the lights turn on on the Neey?

[@todamnbad]

@@OffGridGarageAustralia I checked the leads and all is good, I have a solid blue and blinking red (center led)

[@OffGridGarageAustralia]

@@todamnbad The red means fault?

[@todamnbad]

Well crap, I have no idea what I am doing wrong, I put the red and black on the external power supply, B1-B4 on the same place the BMS leads are, I get power to the balancer and I van connect to it with the app but I get no readings on the cells, I think its because I don't have a negative on the battery to complete the connection but im not sure how I would do it since I am using an external power supply

[@OffGridGarageAustralia]

@@todamnbad Ahhhhh, yes, that is the think if you don't have a battery connected correctly, the reading are off. See my other video where I did the test with the QUCC BMS and made the same mistake leaving the B- off the battery. Well, get some AA batteries and build your battery with it, connect the BMS as you would and it should work. Just don't charge it with normal AA batteries 😉

[@kenl6880]

Couldn't you connect the boost converter to the output of the BMS rather than the battery directly and allow the BMS to do its job of protecting the battery from over discharge? The boost converter would then be powered on by the charge voltage used to "wake-up" the BMS, and the BMS would disconnect the boost converter and itself, should the voltage drop below LVD. Given that you mentioned another BMS that achieves this same result without a boost converter, this may be irrelevant. Edit: I also believe this would protect both the boost converter and BMS from under-voltage caused by the parasitic draw of the boost converter.

[@DavidHalko]

If the BMS will not work without the boost converter, how can you connect the boost converter to the output of the BMS? The BMS would never turn on, therefore the boost converter would never supply 48v to the BMS to become operable The boost converter is needed to function before the BMS can function.

[@kenl6880]

@@DavidHalko The change I'm suggesting is to move the negative jumper for the boost converter from the battery negative to the P- of the BMS. When you supply the charge voltage to the P- of BMS, even though it is off to begin with, it should also power the boost converter as well which would then create the 48v supply on the B+ wire which the BMS needs to start. Maybe we can get Andy to try this in his next video. I haven't done it myself and I'm happy to be proven wrong. Being wrong means we're learning.

[@OffGridGarageAustralia]

That could work. It's just for a test. I'm not expecting anyone to build a real system with that. It was more to explain and test if it would work.

[@1bigsyd]

Lol this came up in my feed and I thought..I recognise him…I’m a Mitsubushi phev owner ..also into thes kind of thing

[@OffGridGarageAustralia]

Hey great, welcome back. Quite a few PHEV owners here actually!

[@ocular57]

Is there going to be a JKBMS for 4S 12V packs? True or False

[@ocular57]

Can the new JKBMS 8S 2A 200A unit be driven by a 12V to 24 DC-DC converter as well to make it suitable for 12V 4S?

[@ocular57]

All the JKBMS from Hankzor now have a minimum LiFePO4 cell no of 8 in there complete range, in instructions says you need a minimum voltage of 20V. So a DC DC converter of 12-24 should work?

[@errolives8724]

OOPs description states bms but it is juat a balancer..sorry

[@OffGridGarageAustralia]

The JK BMS is a full BMS.

[@Fly-To-The-Hell]

I forgot my password how I can reset my bms if you know please teach me

[@alexmaurer]

Andy you must change the battery of your UT210D 🙆‍♀️

[@OffGridGarageAustralia]

Nahhhhh, not again! It's fine until it dies. We have already tested that. No error in measurement with low bat signal...

[@chrisfryer3118]

cheers from a 24volter

[@OffGridGarageAustralia]

I need to think about everyone!

[@mahmutkurt9884]

thank man,

[@ImanAcademySE]

I meant to say 3.55 or 3.612

[@awesomusmaximus3766]

I'm too used to lead acid I still feel skittish going under 70%

[@OffGridGarageAustralia]

Hahaha, that's great!

[@raymondcasso7966]

See... you just needed to give it time.

[@KevIsOffGrid]

The issue here is when you have low voltage disconnect overnight. Then the boost converter is draining the cells even lower, but you can always adjust the LVD to like 2.8v/cell to give you room for further discharge, with a big pack on solar when the most you'll have to wait for more charge is a matter of hours it will be fine. However a pack recharged by say a wind turbine could have to wait weeks for power. However don't know anyone with only wind and no solar.

[@kenl6880]

I think he could've connected the boost converter to the output of the BMS rather than the battery directly. The boost converter would then be powered on by the charge voltage used to "wake-up" the BMS, and the BMS would disconnect the boost converter and itself should the voltage drop below LVD. Just a guess. I haven't tried it.

[@OffGridGarageAustralia]

How do you start the booster if it sits on the output of the BMS and both are off though? At 0.1A draw for the booster is will use 2.4Ah per day if there is no charge coming in.

[@stupidmonkeykev]

@@OffGridGarageAustralia it won't. But the drain won't be an issue for the majority of users; just something to be aware of.

[@kenl6880]

​@@OffGridGarageAustralia Maybe I don't understand how the battery charges through the BMS. I believe if you put a power supply voltage on Battery + and P- like you would to charge the battery normally, it would provide power to the boost converter, which in turn, would generate the voltage the BMS needs. Both would be powered on initially by the power supply until the BMS activates and allows power to flow through the P-, at which point the charger/power supply could be removed and it would continue to run on battery until the BMS hit LVD causing both to shut off again.

[@danieljohansson5240]

Hi, Thank you for your fun and interesting videos. I have made the same setup as in this video but with larger cells: 12v (4s) EVE 280Ah JKBMS (JK-BA2A24S15P) 12V -> 24V booster (as recommended by seller) Everything works BUT the Current (A) is way off... JK BMS shows current as 2.1A when Victron Smart Shunt says 3.8A If I then calibrate the JKBMS to 3.8A everything looks good BUT when ampere is lower or higher it drifts way off (for example Victron says 8.9A, the JK BMS shows only 7.2A) Any ideas to why? Have anyone experienced the same problem? Anyone who can test this with your setup? Thanks!

[@angelobautista5]

Hi. Just want to know if your booster should also be rated same with the load? Ex. 3kw load = 3kw rated booster?

[@danieljohansson5240]

@@angelobautista5 the booster is just to provide the bms with correct voltage (If I remember correct I used a 12V to 24V booster (2A)

[@angelobautista5]

Thanks @@danieljohansson5240 . My set up is 24v 8s and I've also read some comments here that he find no issue using it in 7s. But just in case mine doesn't work on 8s, it's good that the booster don't have to match the load. 👍

[@gregmeredith9596]

It works but not KISS

[@ralph9987]

this method is a test and will most likely be very unreliable. the more components you add to a system, the less it becomes autonomous and unproblematic. Your bias towards this BMS is interesting and i wonder why you are so desperate to push this BMS, even at the risk of offering unreliable solutions. is there a disclosure needed for transparency here Andy?

[@OffGridGarageAustralia]

Yes, that was a test as requested by viewers. Not many will set this up in a working environment. As always, I'm sharing my experience here and not pushing anything. This BMS is the best I have tested so far. And that's what others have confirmed. If you know anything else, don't hold back. I'm interested to listen to your conspiracy theory... BTW, I paid full price for it. Want to see the receipt?