That was a lot of fun this morning to chat with you during the premiere. We should do this more often. I can make longer videos so we have more time 😁 We had over 500 viewers during the stream, that is amazing! Don't forget, I'll explain exactly what happened with the JK-BMS in the very next video, coming on Saturday morning 5am AEST. Thanks a lot again for all your support. Love you all!
@@jakobgode Hallo Jakob, hab gerade mal gemessen, die beiden Terminals sind jeweils 18mm breit, also 2x 18mm plus 1-2mm Platz noch dazwischen. Ich bekomme dort sogar zwei 70mm Kabelschuhe nebeneinander drauf.
Hello Andy. André from Norway here; Could I ute this BMS for my 3S build? -For my boat I will build four 12V Lithium ion 3S7P batteries. LEV50 Cells from EV Peugeot i-on 11,25V nom 8,25 - 12,3V range each of the four battery pack will have 350Ah and will be connected in parallell, totally 1400Ah
I have just set up one of these JK BMS's. It was supplied without an on/off switch. From previous setups of a JK 48v BMS I know that you can apply a voltage across the P and B terminals to activate the BMS. In the past I had used a 9v PP3 battery to do this but I have just seen a TH-cam video showing a very easy alternative. Set a multimeter to the diode test setting and touch the +VE lead to the B contact and the - ve lead to the P contact. The BMS then starts - quick and easy!
Very COoL. I was LITERALLY just looking at this model. So, this is clearly the 2nd best YT video I've seen in my entire life. Just saying Thank you for your efforts and "taking one for the team". p.s. Very nice production value (post edits etc)
I will be building a 24v 280ah battery very soon, I was leaning towards the overkill solar bms till I watched this video, I will be going with a jk bms now, thanks for the very informative videos, keep up the great work, enjoy your videos!
Thank you very much for your review. I just ordered one of these and they are on SALE right now. With your discount I only paid $109 USD. Thanks again.
Andy i must thankyou for these videos. Your info has been so helpful. Ive just completed building a 280ah 4 cell lifepo4 battery with the jkbms. This is to replace 2 lead acid batteries in our motorhome. I chose the jkbms to be able to connect to my rasberry pi running the cerbo gx, again thankyou to your videos for helping me get that working flawlessly. Next step is the peter inverter, and hopefully pick up on the rs485 to the raspberry pi. Keep up the great work on your channel.
Thanks a lot for your kind feedback. I appreciate that. Also, as an alternative, have a look at these Xijia Inverters on my website. They are very robust and at least as good as the Peter.
@@paulhowes3788 Not from AliExpress through the links on my Homepage? They come with a universal plug which fits all standards. off-grid-garage.com/inverters/
Finally I found a nice youtube channel with good test. One of myDaly bms gave up...and so Im looking for something better for my 280 AmpH battery . Thanks for this test, an order will be done soon.
At 6:28 you read that it doesn't support series connections. I'm looking for a clerification on this. This is to say I can't series up two 8s 24v drop ins for 48V? I thought a B2A24s20p or B2a20 would work. Seems a pretty basic 48v set up to me. What am i missing?
I received mine today and super excited to get it hooked up. Mine didn't come with a display, but only a power button. Not a big deal for me, but just informational. Not sure why this was different other than Hankzor likes Andy better. I don't blame them for that. haha Thank you for doing all of these tests to provide us with data to make informed decisions!
Hello Mark! I just received mine with power button also instead of a display. Just to make sure, is this power button will be plug on the display port to start the BMS? Thanks in advance.
If the inverter has an LC input filter without clamping diode, the BMS may have gotten zapped by the filter inductor exceeding one of the FETs' avalanche energy when the BMS disconnected.
Thank you. Your videos are starting to give me the confidence I need to take on the next project. Currently most of my house is solar powered on a 48v system, now my sights are on my moth balled 1979 MGB limited edition. I'd like to take it electric for cruising about town. I have subscribed and will review all your postings!
Thanks for introducing to this very nice BMS Andy! Ordered this after getting inspired by your video. Had to get it to India from Hankzor through a friend in an intermediate country as aliexpress does not work here (Duh!) Awesome BMS!
No idea why I waited so long to watch this, I am sorry. You just made me buy one of these and the same display. I've come to hate the xioxiang app and my existing BMS is only 30A anyway :P Cheers Andy!! :)
Serie/Parallel connection for communication/functions purposes between BMS and subsequent data to inverter/chargers. More than one RS terminal needed. That's my best guest. 😉
Hi Andy, I think those EVE LF105 are rated for only 1C continuous discharge. 3C rating is only for long pulse discharge, may be 3 minutes or something. Can't wait for the magic smoke trouble shooting video. 4S capability in JK is great. Thanks for the review.
Well the teaser video had me excited to see what you blew up. Have to wait until the next video to find out all the details. Anyway, I enjoyed the testing and had a chuckle as you decided to keep pushing it after the magic smoke appeared. I was surprised the BMS was still functioning after all that. Things tend to not last very long when run at the maximum. Had you kept it just under 200A it might have been fine.
I got mine today. I was wondering what to do about using the heating pad option, do to the fact they give no connector to use the heating Pad port. 😕 Can someone point me to a usable diagram or video that actually tells how to make this work?
@off-grid garage , Andy could you try to see if the button on the display is a simple contact. Doing a continuity check on the cable with the button released and pressed. If it's a simple contact it's detectable. The display is not very useful, but a DIY 1$ button could be very beginners friendly.
I like that you have to option to change the resistance in the balance leads. If I had this bms on my 280 ah cells I would be more likely to use it but ehh. Wouldn't make a huge difference other than minut accuracy. Well don't video Andy. Thankyou for sharing as always
I'm not surprised that the cables stay cool. This is the formula for calculating the cable size: Current (Amps) x length (meter) x 0,2 = cable (mm²). So calculating back: 16mm/ 0,2m/0,2=400A. So the length has a huge impact on the capacity.
Cool video, Andy. Looks like they use thermal pad/adehesive between the mosfets and metal case, hence the bending. This allows the heat to dissipate into the metal case and remove it from the mosfets. Has to be a tight contact for it to work effectively. EDIT: Passive Cooling.
Hi Andy, it looks like Hankzor is no longer honouring your coupon code :( I'm sure this video is still sending lots of customers their way however.... p.s. Thank you so much for all your work, it's such a privilege having a fellow off gridder making content here in the Australian context that is so informative
The bus bars are coming with the cells when you order them, the ring terminals, I buy locally as they are heavy duty lugs. I have some of this material also on my website: off-grid-garage.com/battery-accessories/
Hi Andy, I like your videos but what is a bit frustrating when researching what to buy, you never list the exact model number anywhere obvious. Good to know that this is a JK 42-8s BMS but which version? How many Amps can it handle? You say it in the video at 4:30min but you never know if you have the right video from the start. Would be great if you could list the exact product code in the video description as this would be immensly helpful. Thanks in advance!
Thanks for the installation guide. Very usefull. I noticed my BMS app doesn't show any decimals for "calibrating curr." value, but maybe they have changed this in the app lately?
Excellent video - thank you! Mine is on the way for my first battery build, also a 105 ah with Eve cells. Can anyone tell me if the question was ever resolved as to if this BMS can be used in parallel with other batteries?
I assume that the emergency switch is like the battle short on army generators, bypasses safety checks that would prevent the generator from running and causing damage. Sometimes you just need power. I assume this bypasses the temperature restrictions and settings
Excellent video Andy, many thanks. I dont know if yourself or anyone else might know if there is an issue for having the software mod loaded onto GX touchscreen for batteries with integrated BMS and still wanting to use a Victron BMS ver2 with victron batteries. Not as the same time but using either a Victron lithium set or integrated BMS batteries?
Great test & review of the JK BMS Andy and I like many others have purchased one after watching your excellent video. I recently upgraded my inverter charger to 4.2 Kw from 2.5 Kw and now I’m getting this “Protection (CPUAUX Anomaly)” warning repeatedly as are many others with zero response from JK or their distributors to our complaints. Can anyone shed any light on what the cause might be and possible remedies? Cheers & Beers🍻
I have this BMS almost a month now... testing daily and playing with very satisfactory results. The odd that observed is in total current of the battery, when the battery is charged and discharged simultaneously. Current sensor fail to display real number (zeros), can't calculate load and charge and report error with yellow text "Protection (Current sensor anomaly)". I dont know if my BMS is faulty or something wrong related to software or firmware. Fact is, if one of the currents missing works fine. In your test Andy notice you use only one scenario, either charge or discharge not both. Haven't confirm yet if that affect also some other counters too, cycles used Ah etc.
More than a year has passed, how would you rate this bms to work with the 204EVE cells and a load between 1kw and 2kw? 2kw pulsing, induction cookplate in a campervan?
Hi Andy, I have tested the JK-B2A8S20P for use in our AGV-batterypack. For us the SOC is very important to steer the agv in time to a dockingstation for loading. It is not clear which value I can use best for the SOC. Remain battery is what they present in the app but I ̀ m not sure if that is calculated by means of counting coulombs. It looks more like the value is calculated from the voltages. What is your idea about this?
The JK-BMS does definitely Coulomb count and once fully charged it starts counting from there. The SOC value will drift over time if not fully charged frequently. If you charge it in a dock it should be fine and fairly precise, so you can read the SOC directly and use it for your system. The remaining capacity is just a calculation the BMS does and displays, from what you have set as maximum capacity.
great videos thanks. I'm a little confused why you like this BMS so much when it blew up? Shouldn't the Over Current protection kicked in and safely disconnected the load without blowing the output? Its rated to disconnect up to 350A? This would seem like a fail? Also if the unit is getting hot at 200A should it have active cooling built in?
Absolutely. This was the first device on the market and we have raised this issue with the manufacturer so they can choose different FETs in the future. It has passive cooling and 200A constant current is stretching it. 200 Chinese amps are like 150 real world amps 😊 It is still the best consumer grade BMS out there.
hello Andy i’m building 50ah battery box whit eve cells but i don’t know what bms to install i have 4 cell is ok the 8s-20s 60ah or i need to find 4s bms thanks for your help
If you have a battery with 4 cells in series, you need a 4s BMS. How big this BMS needs to be is dependent on your maximum current you plan to charge or discharge your batteries with. The EVE 50Ah cells are fairly small so a 60A BMS should be sufficient, like the BD6A20S6P for example. Have a look at the 4S JK-BMS I have on my website, they now come with different current rating. off-grid-garage.com/battery-management-systems-bms/
Hi Andy, thanks for all your great videos. I have a question and perhaps maybe a potential test idea? I've read somewhere that the welded stud terminals are not really good for high current draw. You yourself had pointed out the small surface area of the welded studs in your videos. I had an Idea tonight, how about adding copper washers with 11mm ID and 16mm OD, 2mm thick(or 2x1mm) around the base of the welded stud where the original battery terminal is. This would increase the contact area with the busbar and allow for more (or less restricted) current flow resulting in less heat? I could be wrong of course. Also ot sure about mating different metals (copper/aluminium), so nickel plating might be beneficial? Let me know what you think.
Thanks Jan. I have done some high amp testing here on the channel with these cells and the very small contact area of the welded studs (see video below). PERFECT! No trouble, no heat built-up. Seplos put copper washers in their DIY box to be installed around the terminals. Not a good idea. While it increase the surface area, it also increases the resistance and heat. th-cam.com/video/VPQvs-2YYzA/w-d-xo.html
I guess we now have a new test... The Lick Test {Not to be confuse with the archaeological one}. Nice! Love it. Does this one requires a prior use of S.P.A.T. at the right temperature? Inquiring minds want to know!
Aloha Andy! I ordered a JK-B2A8S20P, intending to do an 8S setup with EVE 304Ah cells. However: we ran out of money. Question: can I configure these to use our old 12V 3KW inverter? What if I put 4 pairs of parallel cells in series? Thanks!
Looking forward to seeing what smoked... I reckon it was maybe a current shunt, but will be interested to see. Btw turning off a FET with full current is not a problem in itself to the FET. You may however produce a inductive spike that the circuit around it finds hard to handle.
Hello congratulations for the video! I just saw your video 1 year late! I have since ordered a very large EVE 280K battery pack grade A I have to do a 9S/4P! 30 volts (1120AH) I will obviously balance the cells well before putting them in // for the BMs JK seems very good compared to the daly bms 200A which choice would be better? my big pack is intended for solar storage 4 solar regulators (80A in charge and discharge 125A at 30 volts (COTEK 4000 watt pure sine converter) THANKS laurent france
Hi Andy, this is Russell here from Rio de Janeiro Brazil. Your fan. Do not miss any of your videos. They are instructive and nice to see. I have a question on this JK B2A8S-20P. I am using them to made 5 12VDC DIY Lifepo4 batteries. I want to know how can I get the BMS to send me a 12V signal in two cases. 1- When the BMS cuts the battery charge due to "Cell OVP" (cell Over Voltage Protection) and 2; when the BMS cuts the discharge of the battery due to "Cell UVP" (Cell Under Voltage Protection). Is it possible to get these signals in the one of the BMS connectors?
@@OffGridGarageAustralia Hi Andy, I don't think I have ever seen Chinese electronics without silicon wire. I bought a 10,000/18,000kw Chinese inverter and when I looked inside and saw the cable to the output terminals, like you I said no way, then discovered the American AWG is completely different to the Silicon AWG. And you yourself commented that it was cold when you ran 200Amps in the test where you got magic smoke from the JK BMS, By the way, I am Qualified electronics engineer with 50 years experience, retired now 70 years old and although it's not good practice to leave it, I would leave the dead FET if you do not have a hot air re work station. Keep up the excellent video's, you are like everyone's best friend . Bob Uk
It is unfortunate that BMS could not handle shut-off for the 200+A test. That is a black mark on the BMS. Despite that, this seems like a solid BMS for 12V set-ups with 1500W (or smaller) inverters. (Note: I would never run a BMS at 100% of it's ratings. My designs would leave a minimum of 25% headroom.) JK has made itself the top BMS vendor in my book. I am not sure why anyone would pick a different BMS for a DIY battery. BTW: I avoid 12V systems if I can, but many folks like to stay with 12V for mobile installs. It would be nice to see a 300A 4S BMS that could drive full power on a 3000W inverter. (300A is a lot more current than I like to deal with....and that is one of the big reasons I avoid 12V.)
Agreed, I wouldn't expect it to run for very long at full rated load, but it still should have cut off gracefully. Very curious to see what actually burned up.
Really curious about the restriction that it can't be used in parallel. I encounter serious issues when I connect the RS485 while the other battery is connected as well. It starts showing phantom currents, even if the MOSFETs are off, if you can get them off. The discharge won't switch off as long as it notices this (phantom) incoming charge. I will replace the JK with a Seplos to investigate how that works.
So these MOSFETS have a 40V max voltage between Drain and Source. If you series connect these BMSes and one turns off you can potentially come very close to this voltage for the remaining BMSes. In parallel, they are worried about high currents from one battery bank to another. I'm in discussion with Hankzor about this 'problem'. Well, I don't see it as a problem. I'm having a few Seplos devices coming in in 2-3 months. I expect their BMS is not as good as the JK. Not by far...
@@OffGridGarageAustralia I'm really looking forward to your tests. I would like to see how you connect all these BMS to your Victron gear. Seplos supports that natively. Maybe you'll see some strange behavior as well. I like the JK's balancer, but without communication it's useless for me. Maybe I'll run it as a balancer in parallel to another BMS (without connecting P-). Thanks for the good stuff, as always.
@@keyem4504 JK has the RS485 port which can be easily connected to Victron's VenusOS. There are divers and manual available. But for what reason would you want that? Just to see the lowest and highest cell voltage on the screen?
@@OffGridGarageAustralia There is some benefit on connect BMS to inverter but the BMS need to have that function, in some situation like battery/bms temp is high, then the BMS can tell the inverter to lower down charging current instead of shut off the BMS directly, some BMS have build in current limiter function if anything wrong with the inverter or BMS it will limit the current to 10a instead of cut off the power straight away.
@@wenhaowong5549 inverters usually don't charge a battery. It's the opposite, batteries deliver power to the inverter through the BMS. This power is determined by the load connected to the inverter. And this can't be controlled by the BMS. There is nothing you can slow down in this process. If one cell gets to high or low, the BMS will shut down power anyway and the inverter will turn off. So again, why does the BMS need to talk to the inverter?
Hello wonderfull video. I bought the same bms i d like to connect with a computer with rs485 and can. Did you do ? could do a video about rs485 connexion ? Thanks.
Well done. Please, do a video of opening up that JK to see what smoked. Is there a C or F option for reporting temps? If you have the bluetooth display, why would you need the other display? Bluetooth seems to provide a lot more information, right? Thanks for sharing
Wow. Record speed shipping, i ordered mine on the 9th may, and its in my hot little hands on the evening of the 20th! I ordered the non heating version, but they sent the heated version anyway, maybe they just make the bms all the same, but just include the wires and plug with the heated version as the port appears to be there on the bms anyway. Since i have it now i might as well connect it right? It would be helpful if they showed a diagram as theres a ring terminal with a few green wires as well as one red and one black wire and they are so small!
Good afternoon! I purchased BMS JK-B2A8S20P at TAO BAO. Unfortunately, the seller did not include a user manual. Can you recommend how to activate BMS? There is a short cable with two wires and a connector that fits into the display port.
Hi Andy, I bought this BMS with 4 cells of EVE LF280K 3.2V 280Ah LiFePO4. Can it handle 3000watt inverter? I am new to all this amps, amp hours, 2C, IC, thanks
Hi Andy, Hey all! Just thought I shed some light on my experience of this bms. All is great till you run into an issue with it not turning on or off. When you do finally get it to start it will not connect to phone app. It so happens that one of the diodes for the speaker causes the unit to malfunction. I had this issue with two of the bms's I purchased. I was advised by the guys from JK to remove this diode. Once done problem is solved! Though this mod causes speaker to no longer function. I am not sure if this issue is still occurring with current stock they are selling. Also running multiple battery banks using the same bms is now possible providing you use a T Class rated fuse. Please refer to the Aliexpress listing for details. Was not accounting for this additional cost but as long as everything works all is good i guess? I hope this is helpful for other viewers looking at purchasing this for their application.
@@UsernamePassword85 I do get the three beeping noises! And then the light just blinks once a second. The Bluetooth symbol on the app always shows an x, like it is not turned on.
Love your vids....You are helping me understand the charging processes of LifePo4 batteries. I just purchased two SOK Brand 206 Ah "H" Series LifePo4 batteries to replace my older flooded deep cell batteries. I want to really understand how to charge and take care of my new purchase. Also I'm in the market for a new clamp meter and wondered how you like your UNI-T Clamp Meter? Also what model meter is it? I couldn't quite see the model in the video. Would you purchase that same model number again or would you get a different brand and/or model number? Thanks again for informative and humorous content!!! Mark
That was a lot of fun this morning to chat with you during the premiere. We should do this more often. I can make longer videos so we have more time 😁 We had over 500 viewers during the stream, that is amazing!
Don't forget, I'll explain exactly what happened with the JK-BMS in the very next video, coming on Saturday morning 5am AEST.
Thanks a lot again for all your support. Love you all!
Hi Andy glaubst du, dass Rohrkabelschuhe 50mm2 auf M6 auf alle 4 Anschlüsse vom BMS passen?
@@jakobgode Hallo Jakob, hab gerade mal gemessen, die beiden Terminals sind jeweils 18mm breit, also 2x 18mm plus 1-2mm Platz noch dazwischen. Ich bekomme dort sogar zwei 70mm Kabelschuhe nebeneinander drauf.
@@OffGridGarageAustralia Vielen Dank 👍🏻
Hello Andy. André from Norway here;
Could I ute this BMS for my 3S build?
-For my boat I will build four 12V Lithium ion 3S7P batteries.
LEV50 Cells from EV Peugeot i-on
11,25V nom
8,25 - 12,3V range
each of the four battery pack will have 350Ah and will be connected in parallell, totally 1400Ah
@@OffGridGarageAustralia Hi sir
Eve LF105ah brand new cell made by 12v pack need to Balance machine or jk bms is enough?
I have just set up one of these JK BMS's. It was supplied without an on/off switch. From previous setups of a JK 48v BMS I know that you can apply a voltage across the P and B terminals to activate the BMS. In the past I had used a 9v PP3 battery to do this but I have just seen a TH-cam video showing a very easy alternative. Set a multimeter to the diode test setting and touch the +VE lead to the B contact and the - ve lead to the P contact. The BMS then starts - quick and easy!
Very COoL. I was LITERALLY just looking at this model. So, this is clearly the 2nd best YT video I've seen in my entire life. Just saying Thank you for your efforts and "taking one for the team". p.s. Very nice production value (post edits etc)
Andy, Ty for such wonderful work. I love the interactive live chat section! Keep up the good work!
Thanks a lot for tunning in this morning. It was great, I really enjoyed it.
@@OffGridGarageAustraliadear sir Daly bms or jk which one better please tell me
@@Bokul112 JK, 100%!
@@OffGridGarageAustralia thanks sir
@@OffGridGarageAustralia sir 100% mean?
Daly smart bms with active balancer is good ? For 12v 105ah
I will be building a 24v 280ah battery very soon, I was leaning towards the overkill solar bms till I watched this video, I will be going with a jk bms now, thanks for the very informative videos, keep up the great work, enjoy your videos!
Thank you very much for your review. I just ordered one of these and they are on SALE right now. With your discount I only paid $109 USD. Thanks again.
Thanks Jason, that is a really good price for a great product.
Absolutely awesome vid,was excited the whole time.
Thanks!
Thanks a lot James, much appreciated.
Andy i must thankyou for these videos. Your info has been so helpful. Ive just completed building a 280ah 4 cell lifepo4 battery with the jkbms. This is to replace 2 lead acid batteries in our motorhome. I chose the jkbms to be able to connect to my rasberry pi running the cerbo gx, again thankyou to your videos for helping me get that working flawlessly.
Next step is the peter inverter, and hopefully pick up on the rs485 to the raspberry pi.
Keep up the great work on your channel.
Thanks a lot for your kind feedback. I appreciate that. Also, as an alternative, have a look at these Xijia Inverters on my website. They are very robust and at least as good as the Peter.
@@OffGridGarageAustralia unfortunately xijia isn't available to the UK
@@paulhowes3788 Not from AliExpress through the links on my Homepage?
They come with a universal plug which fits all standards.
off-grid-garage.com/inverters/
Outstanding vids Andy. So many thanks for your lessons. BMS Jk working perfect here in Brazil !!!
Thank you. Great job 👍
Wow! I didn’t realise you could have so much fun testing a bms and learning.
Finally I found a nice youtube channel with good test. One of myDaly bms gave up...and so Im looking for something better for my 280 AmpH battery . Thanks for this test, an order will be done soon.
Thank you Ralph and welcome to the channel.
Nice, just ordered one for my 4s setup for offgrid camping. Thanks Andy for the review !
Great video Andy , I love watching your reviews and experiment , great stuff 😂
Thanks Andy- awesome! LOVE your work!
Mine is on the way, so the caravan will soon have an upgrade! Fabulous!
At 6:28 you read that it doesn't support series connections. I'm looking for a clerification on this. This is to say I can't series up two 8s 24v drop ins for 48V? I thought a B2A24s20p or B2a20 would work. Seems a pretty basic 48v set up to me. What am i missing?
Great Video, Thanks. I'm a little bit confused 25:10 . At the Initial state, Remaining capacity 77 AH get from..
Thanks for come back to us, the poor guys!
you live on the edge Andy. Good job.
I love all you detailed videos thus far and I’m enjoying and learning at the same time.
Awesome, thank you!
27:51 is beautiful. 🤤That is very comforting to see it in action, no guesswork to know if its balancing or not.
I put two on order LOL! Cant wait for the review!
Me too...
Why dont you build your own bms
@@t3chb0y67 I am not that smart
@@jameshelmuth5268 I didn't notice you cant run in parallel . This might be a problem.
@@UsernamePassword85 What exactly is meant by "can't use them in parallel"?
I received mine today and super excited to get it hooked up. Mine didn't come with a display, but only a power button. Not a big deal for me, but just informational. Not sure why this was different other than Hankzor likes Andy better. I don't blame them for that. haha Thank you for doing all of these tests to provide us with data to make informed decisions!
Hello Mark! I just received mine with power button also instead of a display. Just to make sure, is this power button will be plug on the display port to start the BMS? Thanks in advance.
Yes, that’s correct. The plug will only fit one of the ports so you can’t go wrong
So excited for 4S BMS, been waiting for these features without magic smoke!
Had to look this one up: Coulomb counting is a reliable technique to predict remaining battery capacity. 👍
If the inverter has an LC input filter without clamping diode, the BMS may have gotten zapped by the filter inductor exceeding one of the FETs' avalanche energy when the BMS disconnected.
"I could watch this all day long" Me to! it's hard to find a TH-cam video that can capture my attention for 45 minutes!
Thanks a lot Travis!
I love the under temperature test!
Danke!
Thanks a lot Peter!
I have to thank you! Gut, dass wir dich haben :)
That BMS looks amazing. Now we need a 48V version of it. It looks great. Now we must check the charging process.
They are Available up tp 24S :)
Thank you. Your videos are starting to give me the confidence I need to take on the next project. Currently most of my house is solar powered on a 48v system, now my sights are on my moth balled 1979 MGB limited edition. I'd like to take it electric for cruising about town. I have subscribed and will review all your postings!
Thanks for introducing to this very nice BMS Andy! Ordered this after getting inspired by your video. Had to get it to India from Hankzor through a friend in an intermediate country as aliexpress does not work here (Duh!)
Awesome BMS!
OKAY I believe I;'m sold on this one. Perfect for a small 4s 120 amp battery to run my 12vdc driveways lights.
No idea why I waited so long to watch this, I am sorry. You just made me buy one of these and the same display. I've come to hate the xioxiang app and my existing BMS is only 30A anyway :P Cheers Andy!! :)
Serie/Parallel connection for communication/functions purposes between BMS and subsequent data to inverter/chargers.
More than one RS terminal needed.
That's my best guest. 😉
Hi Andy, I think those EVE LF105 are rated for only 1C continuous discharge. 3C rating is only for long pulse discharge, may be 3 minutes or something. Can't wait for the magic smoke trouble shooting video. 4S capability in JK is great. Thanks for the review.
You're right. 3C is only for 30S. Still very good and maybe worth a test.
@@OffGridGarageAustralia Yes very good test indeed. And ahh I missed the Premiere and the live Chat. dozed off for a while, it was 1AM here.
Fantastic Video. Very instrutive for me. Thanks
Did you find out what JK is talking about not being
able to hook this up in parallel?
Thanks for your work
Dave
Well the teaser video had me excited to see what you blew up. Have to wait until the next video to find out all the details. Anyway, I enjoyed the testing and had a chuckle as you decided to keep pushing it after the magic smoke appeared. I was surprised the BMS was still functioning after all that. Things tend to not last very long when run at the maximum. Had you kept it just under 200A it might have been fine.
Are you still planning to do a video where you review your Charge Controller settings? Would love to know your settings!
I’m definitely getting one of these for my campers solar setup
Yahoo love the info funny stuff well done JK I have to get one cause I have no BMS right now thank you Sir
I got mine today. I was wondering what to do about using the heating pad option, do to the fact they give no connector to use the heating Pad port. 😕 Can someone point me to a usable diagram or video that actually tells how to make this work?
@off-grid garage , Andy could you try to see if the button on the display is a simple contact. Doing a continuity check on the cable with the button released and pressed. If it's a simple contact it's detectable. The display is not very useful, but a DIY 1$ button could be very beginners friendly.
I'll have a look.
I like that you have to option to change the resistance in the balance leads. If I had this bms on my 280 ah cells I would be more likely to use it but ehh. Wouldn't make a huge difference other than minut accuracy. Well don't video Andy. Thankyou for sharing as always
Informative as it is informative as usual. Thanks for your videos!
vraiment impressionnant ce test ! surtout que j'ai sursauté aussi quand le mofset a brulé 😃
Looking forward to the explanation of the pop and smell.... :)
I'm not surprised that the cables stay cool. This is the formula for calculating the cable size: Current (Amps) x length (meter) x 0,2 = cable (mm²). So calculating back: 16mm/ 0,2m/0,2=400A. So the length has a huge impact on the capacity.
I picked up two for my projects. Thanks.
Great, you won't be disappointed.
Cool video, Andy. Looks like they use thermal pad/adehesive between the mosfets and metal case, hence the bending. This allows the heat to dissipate into the metal case and remove it from the mosfets. Has to be a tight contact for it to work effectively. EDIT: Passive Cooling.
Hi Andy, it looks like Hankzor is no longer honouring your coupon code :( I'm sure this video is still sending lots of customers their way however....
p.s. Thank you so much for all your work, it's such a privilege having a fellow off gridder making content here in the Australian context that is so informative
Thanks a lot. The discount was only for a limited time, I believe. It may have expired.
can you share where you get your bus bars @32:55 and 50x8 and 70x8 terminals @14:50 ?
The bus bars are coming with the cells when you order them, the ring terminals, I buy locally as they are heavy duty lugs. I have some of this material also on my website: off-grid-garage.com/battery-accessories/
Hi Andy,
I like your videos but what is a bit frustrating when researching what to buy, you never list the exact model number anywhere obvious. Good to know that this is a JK 42-8s BMS but which version? How many Amps can it handle? You say it in the video at 4:30min but you never know if you have the right video from the start.
Would be great if you could list the exact product code in the video description as this would be immensly helpful.
Thanks in advance!
Thanks for the installation guide. Very usefull. I noticed my BMS app doesn't show any decimals for "calibrating curr." value, but maybe they have changed this in the app lately?
Excellent video - thank you! Mine is on the way for my first battery build, also a 105 ah with Eve cells.
Can anyone tell me if the question was ever resolved as to if this BMS can be used in parallel with other batteries?
Thanks, nice video! Helped a lot.
Thank you.
Thanks Andy, good test
Thanks for the making the video. Do you know what the quiescent current is for the BMS?
I have been using the same BMS on my system since the end of last year with no problems
How? These have only just become available?
I have too bought the same exact bms like 4 month ago, they were on the market for some time already
I assume that the emergency switch is like the battle short on army generators, bypasses safety checks that would prevent the generator from running and causing damage. Sometimes you just need power. I assume this bypasses the temperature restrictions and settings
Thank you. So good
Thank you!
Excellent video Andy, many thanks. I dont know if yourself or anyone else might know if there is an issue for having the software mod loaded onto GX touchscreen for batteries with integrated BMS and still wanting to use a Victron BMS ver2 with victron batteries. Not as the same time but using either a Victron lithium set or integrated BMS batteries?
Am I seeing smoke at 0:55 and again at 1:02? I have a feeling some electronics were harmed in the making of this video. Oh, this is going to be good.
Lol
Great test & review of the JK BMS Andy and I like many others have purchased one after watching your excellent video. I recently upgraded my inverter charger to 4.2 Kw from 2.5 Kw and now I’m getting this “Protection (CPUAUX Anomaly)” warning repeatedly as are many others with zero response from JK or their distributors to our complaints. Can anyone shed any light on what the cause might be and possible remedies? Cheers & Beers🍻
Heya oh wouw that's a very nice test with some smoke too
hello on this bms there is also a heating pad output, for cold places (camper van), a video with this element would be interesting.
I have this BMS almost a month now... testing daily and playing with very satisfactory results. The odd that observed is in total current of the battery, when the battery is charged and discharged simultaneously. Current sensor fail to display real number (zeros), can't calculate load and charge and report error with yellow text "Protection (Current sensor anomaly)". I dont know if my BMS is faulty or something wrong related to software or firmware. Fact is, if one of the currents missing works fine. In your test Andy notice you use only one scenario, either charge or discharge not both. Haven't confirm yet if that affect also some other counters too, cycles used Ah etc.
More than a year has passed, how would you rate this bms to work with the 204EVE cells and a load between 1kw and 2kw? 2kw pulsing, induction cookplate in a campervan?
Hi Andy, I have tested the JK-B2A8S20P for use in our AGV-batterypack. For us the SOC is very important to steer the agv in time to a dockingstation for loading. It is not clear which value I can use best for the SOC. Remain battery is what they present in the app but I ̀ m not sure if that is calculated by means of counting coulombs. It looks more like the value is calculated from the voltages. What is your idea about this?
The JK-BMS does definitely Coulomb count and once fully charged it starts counting from there. The SOC value will drift over time if not fully charged frequently. If you charge it in a dock it should be fine and fairly precise, so you can read the SOC directly and use it for your system. The remaining capacity is just a calculation the BMS does and displays, from what you have set as maximum capacity.
great videos thanks. I'm a little confused why you like this BMS so much when it blew up? Shouldn't the Over Current protection kicked in and safely disconnected the load without blowing the output? Its rated to disconnect up to 350A? This would seem like a fail? Also if the unit is getting hot at 200A should it have active cooling built in?
Absolutely. This was the first device on the market and we have raised this issue with the manufacturer so they can choose different FETs in the future.
It has passive cooling and 200A constant current is stretching it. 200 Chinese amps are like 150 real world amps 😊
It is still the best consumer grade BMS out there.
hello Andy i’m building 50ah battery box whit eve cells but i don’t know what bms to install i have 4 cell is ok the 8s-20s 60ah or i need to find 4s bms
thanks for your help
If you have a battery with 4 cells in series, you need a 4s BMS. How big this BMS needs to be is dependent on your maximum current you plan to charge or discharge your batteries with.
The EVE 50Ah cells are fairly small so a 60A BMS should be sufficient, like the BD6A20S6P for example.
Have a look at the 4S JK-BMS I have on my website, they now come with different current rating.
off-grid-garage.com/battery-management-systems-bms/
thanks for your help and thanks for do this videos
Mine arrived today! Whooo!
Hi Andy, thanks for all your great videos.
I have a question and perhaps maybe a potential test idea?
I've read somewhere that the welded stud terminals are not really good for high current draw. You yourself had pointed out the small surface area of the welded studs in your videos.
I had an Idea tonight, how about adding copper washers with 11mm ID and 16mm OD, 2mm thick(or 2x1mm) around the base of the welded stud where the original battery terminal is.
This would increase the contact area with the busbar and allow for more (or less restricted) current flow resulting in less heat?
I could be wrong of course.
Also ot sure about mating different metals (copper/aluminium), so nickel plating might be beneficial?
Let me know what you think.
Thanks Jan. I have done some high amp testing here on the channel with these cells and the very small contact area of the welded studs (see video below). PERFECT! No trouble, no heat built-up. Seplos put copper washers in their DIY box to be installed around the terminals. Not a good idea. While it increase the surface area, it also increases the resistance and heat.
th-cam.com/video/VPQvs-2YYzA/w-d-xo.html
it appears the 4s-8s doesn't come with the screen.. not sure.. still ordering it.. perfect fit for my growwatt 3000w 24v
I guess we now have a new test... The Lick Test {Not to be confuse with the archaeological one}. Nice! Love it. Does this one requires a prior use of S.P.A.T. at the right temperature? Inquiring minds want to know!
Hahaha, Teddy. I cannot waste any drop of this liquid!
It was in the freezer for 1.5h before doing the test, so temp was OK with 3°C.
Aloha Andy! I ordered a JK-B2A8S20P, intending to do an 8S setup with EVE 304Ah cells. However: we ran out of money. Question: can I configure these to use our old 12V 3KW inverter? What if I put 4 pairs of parallel cells in series? Thanks!
Looking forward to seeing what smoked... I reckon it was maybe a current shunt, but will be interested to see. Btw turning off a FET with full current is not a problem in itself to the FET. You may however produce a inductive spike that the circuit around it finds hard to handle.
Nice work. Thanks.
I was waiting for you to check the amp reading at 200A discharge after you calibrated it.
Nice one. 👍🏻🐸🐸
Hello
congratulations for the video!
I just saw your video 1 year late!
I have since ordered a very large EVE 280K battery pack
grade A
I have to do a 9S/4P! 30 volts (1120AH)
I will obviously balance the cells well before putting them in //
for the BMs JK seems very good
compared to the daly bms 200A which choice would be better?
my big pack is intended for solar storage
4 solar regulators (80A in charge
and discharge 125A at 30 volts (COTEK 4000 watt pure sine converter)
THANKS
laurent france
Hi Andy, this is Russell here from Rio de Janeiro Brazil. Your fan. Do not miss any of your videos. They are instructive and nice to see. I have a question on this JK B2A8S-20P. I am using them to made 5 12VDC DIY Lifepo4 batteries. I want to know how can I get the BMS to send me a 12V signal in two cases. 1- When the BMS cuts the battery charge due to "Cell OVP" (cell Over Voltage Protection) and 2; when the BMS cuts the discharge of the battery due to "Cell UVP" (Cell Under Voltage Protection). Is it possible to get these signals in the one of the BMS connectors?
Hi Andy, again please look at the SILICON AWG chart, the awg7 is over 300 amps, Silicon cable has a much higher strand count
Thank you. I'm just not sure if this is silicon cable. It looks like normal copper cable to me, not silicon fine stranded.
@@OffGridGarageAustralia Hi Andy, I don't think I have ever seen Chinese electronics without silicon wire. I bought a 10,000/18,000kw Chinese inverter and when I looked inside and saw the cable to the output terminals, like you I said no way, then discovered the American AWG is completely different to the Silicon AWG. And you yourself commented that it was cold when you ran 200Amps in the test where you got magic smoke from the JK BMS, By the way, I am Qualified electronics engineer with 50 years experience, retired now 70 years old and although it's not good practice to leave it, I would leave the dead FET if you do not have a hot air re work station. Keep up the excellent video's, you are like everyone's best friend . Bob Uk
It is unfortunate that BMS could not handle shut-off for the 200+A test. That is a black mark on the BMS. Despite that, this seems like a solid BMS for 12V set-ups with 1500W (or smaller) inverters. (Note: I would never run a BMS at 100% of it's ratings. My designs would leave a minimum of 25% headroom.)
JK has made itself the top BMS vendor in my book. I am not sure why anyone would pick a different BMS for a DIY battery.
BTW: I avoid 12V systems if I can, but many folks like to stay with 12V for mobile installs. It would be nice to see a 300A 4S BMS that could drive full power on a 3000W inverter.
(300A is a lot more current than I like to deal with....and that is one of the big reasons I avoid 12V.)
Agreed, I wouldn't expect it to run for very long at full rated load, but it still should have cut off gracefully. Very curious to see what actually burned up.
Really curious about the restriction that it can't be used in parallel. I encounter serious issues when I connect the RS485 while the other battery is connected as well. It starts showing phantom currents, even if the MOSFETs are off, if you can get them off. The discharge won't switch off as long as it notices this (phantom) incoming charge. I will replace the JK with a Seplos to investigate how that works.
So these MOSFETS have a 40V max voltage between Drain and Source. If you series connect these BMSes and one turns off you can potentially come very close to this voltage for the remaining BMSes.
In parallel, they are worried about high currents from one battery bank to another. I'm in discussion with Hankzor about this 'problem'. Well, I don't see it as a problem.
I'm having a few Seplos devices coming in in 2-3 months. I expect their BMS is not as good as the JK. Not by far...
@@OffGridGarageAustralia I'm really looking forward to your tests. I would like to see how you connect all these BMS to your Victron gear. Seplos supports that natively. Maybe you'll see some strange behavior as well.
I like the JK's balancer, but without communication it's useless for me.
Maybe I'll run it as a balancer in parallel to another BMS (without connecting P-).
Thanks for the good stuff, as always.
@@keyem4504 JK has the RS485 port which can be easily connected to Victron's VenusOS. There are divers and manual available. But for what reason would you want that? Just to see the lowest and highest cell voltage on the screen?
@@OffGridGarageAustralia There is some benefit on connect BMS to inverter but the BMS need to have that function, in some situation like battery/bms temp is high, then the BMS can tell the inverter to lower down charging current instead of shut off the BMS directly, some BMS have build in current limiter function if anything wrong with the inverter or BMS it will limit the current to 10a instead of cut off the power straight away.
@@wenhaowong5549 inverters usually don't charge a battery. It's the opposite, batteries deliver power to the inverter through the BMS. This power is determined by the load connected to the inverter. And this can't be controlled by the BMS. There is nothing you can slow down in this process.
If one cell gets to high or low, the BMS will shut down power anyway and the inverter will turn off. So again, why does the BMS need to talk to the inverter?
Hello wonderfull video. I bought the same bms i d like to connect with a computer with rs485 and can. Did you do ? could do a video about rs485 connexion ?
Thanks.
Well done. Please, do a video of opening up that JK to see what smoked. Is there a C or F option for reporting temps? If you have the bluetooth display, why would you need the other display? Bluetooth seems to provide a lot more information, right? Thanks for sharing
Wow. Record speed shipping, i ordered mine on the 9th may, and its in my hot little hands on the evening of the 20th! I ordered the non heating version, but they sent the heated version anyway, maybe they just make the bms all the same, but just include the wires and plug with the heated version as the port appears to be there on the bms anyway. Since i have it now i might as well connect it right? It would be helpful if they showed a diagram as theres a ring terminal with a few green wires as well as one red and one black wire and they are so small!
"I'm the bus bar terminal fix-ar", in Andy's best Arni-Aussie accent..."No wait, I'm the BMS Chef!" Magic 203Amp smoke! 👨🍳🍳
Hi Andy is it possible to Update the Firmware also? I Have the B1A8S10P
Good afternoon! I purchased BMS JK-B2A8S20P at TAO BAO. Unfortunately, the seller did not include a user manual. Can you recommend how to activate BMS? There is a short cable with two wires and a connector that fits into the display port.
How would you start BMS without Power Switch?
With an external 5V voltage as shown here: th-cam.com/video/EtC0mShaRbo/w-d-xo.html
For what purpose is the port labeled GPS on the BMS?
For mobile application like e-bikes, small EVs, boats...
@@OffGridGarageAustralia So, why has the BMS to know its position?
@offgridgarageaustralia; I may have missed it in your follow up video. Is there any problem placing them in parallel, or not?
Replied to your other post already. No issues in paralleling them.
Hi Andy, I bought this BMS with 4 cells of EVE LF280K 3.2V 280Ah LiFePO4. Can it handle 3000watt inverter? I am new to all this amps, amp hours, 2C, IC, thanks
are these moisture resistant. the BMS I'm looking has to live on a salt water sail boat. thoughts?
Hi Andy, Hey all! Just thought I shed some light on my experience of this bms. All is great till you run into an issue with it not turning on or off. When you do finally get it to start it will not connect to phone app. It so happens that one of the diodes for the speaker causes the unit to malfunction. I had this issue with two of the bms's I purchased. I was advised by the guys from JK to remove this diode. Once done problem is solved! Though this mod causes speaker to no longer function. I am not sure if this issue is still occurring with current stock they are selling. Also running multiple battery banks using the same bms is now possible providing you use a T Class rated fuse. Please refer to the Aliexpress listing for details. Was not accounting for this additional cost but as long as everything works all is good i guess? I hope this is helpful for other viewers looking at purchasing this for their application.
I received mine on Friday. The button turns it on and off, but it won't connect to my phone. The app version is 4.7.4.
@@joebalciunas6962 do you get three peeping noises from the speaker? or is it continues ? I am using 4.6.5
@@joebalciunas6962 Just to be clear I am using the android version of the software.
@@UsernamePassword85 I do get the three beeping noises! And then the light just blinks once a second. The Bluetooth symbol on the app always shows an x, like it is not turned on.
@@UsernamePassword85 so am I! The app opens, but the scan button has no activity,
Love your vids....You are helping me understand the charging processes of LifePo4 batteries. I just purchased two SOK Brand 206 Ah "H" Series LifePo4 batteries to replace my older flooded deep cell batteries. I want to really understand how to charge and take care of my new purchase. Also I'm in the market for a new clamp meter and wondered how you like your UNI-T Clamp Meter? Also what model meter is it? I couldn't quite see the model in the video. Would you purchase that same model number again or would you get a different brand and/or model number? Thanks again for informative and humorous content!!!
Mark
Hallo, gute Videos👍.
Ich habe dasselbe BMS gekauft für meinen 24V Akku Block. Läuft das BMS auch mit 24V oder benötige ich einen step down Wandler?
Friend jk 4-8 100ah is good or Daly 4s 12v 100ah bms good
For good balance