BMS Active Current Limiter - Safety Feature or Gimmick?
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- เผยแพร่เมื่อ 30 เม.ย. 2023
- So far, I was not under the impression, that we actually need something like a current limiter when paralleling batteries. From the experience with my battery shelf, I have never seen any high currents going from one bank into another bank unless one was turned off for a while.
Testing and experiencing such an active current limiter though, seems to be a great idea and safety feature: when the charge current hits a set limit (OCP or OC alarm), the BMS will limit the charging current but not disconnect the charger as a BMS without limiter would do.
Such a limiter makes the setup of parallel battery banks extremely safe!
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This feature makes these battery systems almost consumer friendly! So pleased to see this also in the asian modules! So impressed!
I'm in the process of testing all the other BMS as well. Seplos old an new, QSO...
Excellent demonstration. Fantastic BMS.
Oddly, in this scenario I questioned if expansion of many current limiting circuits with differential logic would be even better.. As the number of components increased I cane away with the good old fashioned systems balancing at design along with doubling the robustness of the safety factors.
Thanks Andy, great as usual, love your work!
(We’re living the electric dream in our caravan at the moment, day five away and haven’t bothered turning the gas bottle on. We will likely only do that if we get inclement weather. Hot water, cooking, and heating the van in the morning with reverse cycle A/C is all electric.)
Cheers from central NSW.
Excellent video, thank you!! I was wondering how that works!!! Makes the batteries a lot safer!!
Thank you. It does make it a lot safer. I have tested it many times now and just don't worry about the SOC any more when turning them on.
Have a nice day at work, Andy. Looks like rain is coming down here. Rob is a chap for sending stuff to you.
Pure sunshine up here. Yes, he's a great guy!👍
Extremely good feature.. i noticed this as well charging the other day.
That's a fantastic feature for setup, teardown, or troubleshooting of a system. In normal operation it can also be a saving grace if the charger ever goes berzerk.
Yes, with a careful setting of the charging current in he BMS, this is great and really useful. I would have never thought that...
Hi Andy and Thank you aagain and again for this video,really interesting!
Remember Andy the first time you saw this current limit you did not understand, and found it useless?
I told you it was good, because it protects when connected in parallel (which not the classic BMS, like JBD, JK ...) and limits
your charging current at the end of charging is good!
It's good to have done this test and to share it with all !
Really Andy I think you are the only one to do these important tests, and to give the right explanations, congratulations!
There is one important thing that you will have to test Andy, on the Pace BMS, I know who if the BMS goes into OVP (over voltage Cells or pack)
and that it remains in OVP for a long time, because the voltage and charging current continue to be high.
I could see that when the voltage goes down and comes back to voltage release (cell or Pack) the BMS remains in OVP?!?! (stay in OVP?)
According to a battery pack engineer this would be due to additional protection? which when the BMS stays in OVP for a long time (like 3 or 4 hours) does it go to safety?
And sometimes it can stay very long in OVP, Even if the voltage release has been reached?? (this is not very understandable, but I have seen it several times)
Besides, I have sometimes reset the Bms so that it comes out of OVP mode?
Very interesting? but not completely logical?
Another thing Andy, the only problems I had on this type of BMS (BMS Out of Service) was the current limiting board that burned! (and at the same time burns the main board, so complete replacement of the BMS under warranty) But it was already a few years ago, no more problems, I think they solved this problem... I hope! Anyway thanks again Andy,😁👍
Thank you very much.
Yes, I think you're right with the OVP behaviour of the BMS if it stays there for several hours. I can recall having read something in the manual about it. It requires a discharge current to get out of OVP again at this stage. Just for a moment is enough.
I have tested the current limiter for a few hours and it worked perfectly. The temperature was only hand warm so all seems OK to use this feature for a longer period of time.
Thanks Andy for this and all your other videos! Great approach and always useful.
One thing that I don’t understand is if the current limiter would limit the load on i.e. an alternator such as one in a boat or a caravan, or if the limiter is ”just” limiting the charging going into the batteries. (Hope you understand my poor explanation!)
It's only for charging, Current limiting discharge is not possible
Interesting feature for sure
Thanks Andy 👍
Thank you, Wayne!
Thank you for mentioning the failure mode of a BMS quickly disconnecting Itself from a solar charge, controller under load, which can definitely ruin your precious charge controller. I have learned this lesson, the hard way and I have decided to parallel 5000 µF DC capacitors to the output of my charge controllers, so they will prevent an instantaneous loss of voltage on the output of the controllers.
I also bought a seplos 48 v 100 a bms and I did not know what the inductors were for and now I know. thank you.
I am using Jbdja 300 amp bms’s with high current contactors instead of transistors for extra tough high output, current capabilities. That I monitor with the XiaoxiangBMS app.
I am using eight cells of nmc chemistry in series for a 24 V inverter system that runs as high as 33 V DC! It’s a bit much, but it’s very powerful.
That's actually a good point. If the BMS disconnects under full load, huge spikes could occur and really cause major problems. This feature should prevent this at least when over current protection kicks in.
Very good information with the current limiting safety design. As many battery manufacturer don't recommend more than 2 or 3 in parallel maybe the components can't handle more. For this reason I would still recommend to be careful doing this connection with very unbalanced batteries and of very different capacity. I will still recommend a connection with some resistance in - at least to begin with.
Yes, absolutely. There is no limit with this feature but parallel batteries still need the correct fusing.
@@OffGridGarageAustralia As I have said before the fuses only protect after the electronics is blown. Fuses are not fast enough. If there is enough resistance in the cable so that max current can't be excided that is better. An even better alternative is an inductor that has the correct impedance to block a super fast start current. They will allow just about any DC current but not a fast change in current. Of cause they have the problem with high voltage if the current is instantly cut (like an ignition coil). The resistive solution only causes some small energy losses.
Control not bad. You know that some will not think and just flip the switch. This is a Thumbs up 👍. A good surprise to see 😊
Yes, I really underestimated this feature but especially for beginners, it's a great safety feature.
@@OffGridGarageAustraliaI was about to buy two jk bms but this video (awesome) came up. As I am running Selectronic inverter ax coupled I can’t find a bms that talks to my inverter I was concerned if one bms turned off was I going to get amp spike going to other battery pack. One question though does your pc need to be connected and on all the time with the bms?
Heya, nice that current limiter is a good function
Good day from..... not sunny but cold raining England😅
Is it still raining over there?! 😉
@@OffGridGarageAustralia it's now stopped and the sun is shining....😎
Super cool feature. I want one :)
Me too! 😂
I'm envious of all you guys. I would so much love to finish my little off grid system but things is so expensive here. Require batteries but wow.+- R25 000 😢😢
Buck DC to DC switcher is added across charge disble MOSFET's. (you can see the buck toroid inductor) Without the extra DC to DC converter only option is totally stop charging by charge MOSFET open when charge current gets too high to a low SoC battery pack in parallel with fully charged batteries.
The primary purpose of this is for paralleling battery packs where one pack is very low in SoC relative to other parallel battery packs.
Secondary use is to slow down charging current when poorly balanced cells battery pack is approaching full charge, Make it less likely to totally shut down charging due to a cell overvoltage trip.
You usually need BMS to inverter communication. Without comm it is likely inverter/charger will interpret current reduction as battery approaching full charge causing charge controller to drop to float mode voltage. This usually also stops any further balancing because most cells drop to less than 3.4v with lower charging float voltage.
..
I knew you'd like at least something about our Batteries 😁🥰
I love everything about them 💕
Great feature. It would be great if we could pick all the top features and get one built that includes them all!
Oh, man, we would have the best BMS ever! 😊
@@OffGridGarageAustralia I know right? We can work within this amazing DIY community and show the world what working together can do!
It depends on the total resistance of the wires plus connections plus the internal resistance of the batteries involved. amps = volts / resistance. You postulated 10 volts. Then if the resistance is 0.1 ohm (100 milliohm) then 100 amps. If 10 milliohm then 1000 amps. Reality is likely to be somewhere between those.
The way Seplos BMS is capable of limiting charge current to 10A in the top end of the charge is working very well for balancing/absorbing, in the absense of a real absorption feature. I have set up the 10A threshold so that the last few percent charge takes 30-60 minutes, which is fine for absorbing and balancing (so far, with only 20 cycles on the 280ah pack).
How you setup the point when limiter starts?
@@65mindi monomer overvoltage alarm
Well, that depends on your balancer. Charging with 10A but using the Seplos internal balancer with 100mA won't make a difference. If your cells a well top balanced and matched, it will work though.
@@OffGridGarageAustralia Sure thing. I have an active balancer lying in the drawer ready for installation, but so far my voltage delta is
it's great news 👍
Hey Andy, why you don´t use the neey or heltec smart active balancer? it has the function to set voltage limitis for activate the balancing :) works great here in sunny, cold Germany :)
This would be perfect for a Camper Van installation, where an additional LiFePo4 is installed to an existing Lead Battery in the Car. It would prevent high currents from the Lead Battery or the Alternator to the additional battery. But it seems there is no 4S version available with this feature.
That is a clever feature. Kind of surprising the 3 BMSes in your main system don't have it.
Nah, these cheaper consumer grade BMS won't have that. They just turn off when the current gets too high.
That's beautiful. Doesn't this remove one of the larger concerns for folks who are building a large DIY off-grid system?
Yes, absolutely. You can just add a new battery and don't worry about it. Or if one was disconnected for a while for maintenance, just turn it back on. Done.
I really underestimated this feature.
Cool!
Cool feature, however I wonder if it might interfere with charger algorithms and trip a charger into float mode. This could happen because the perceived battery voltage (to the charger) would be higher than the cell voltage really is. Ultimately it may just cycle between float and bulk/absorption a few times. But in doing this it may also trigger the shunt to register 100% charge.
There's some fun to play with Andy :)
Well, this should not happen because the BMS will send the real battery voltage to the charger through RS485 or CAN. But I'll test it...
@@OffGridGarageAustralia oh of course, yes that's right with your setup. If the BMS was not communicating with the charging system then it may happen, but not in your setup. :)
Want to see if the current limiting circuitry works all the time, regardless if it’s limiting the current or not. That would bring the total efficiency down.
You can turn it on permanently in the Seplos BMS and charge current will be always limited to 10A. This is more for testing purposes but not a permanent setting.
I have 30 x EVE rack batteries with Pace BMS. They each limit to 20A*50V=1kW each. They don't get warm so efficiency must be reasonable.
You only need to limit amps onces you have 3+ parallel batteries. That is if you have only two and one fails, that it won't overload the wiring specs as the output bms will trigger. But if you have 3+ then you'll have 2x+ the rated current and overload the wiring specs. You cover it by fusing.
The feature also prevents the BMS from disconnecting the charger/MPPT.
Saw a Victron 250/100 MPPT that was damaged when the DIY battery bank BMS switched off. Battery was full, inverter AC loads
Must have been an older model. They don't do this any more for quite a while and just go to absorption voltage when the battery is not present.
@@OffGridGarageAustralia When the panels are working, and the batt goes off, where must the power go? MPPT cannot go to absorption voltage ( Bulk charging volts).
The power must go somewhere, the batt not there anymore, can blow the MPPT.
It gets wose ... the problem is system wide like the inverter too.
Inverter will show a DC Ripple. Small one, just a warning. Bad one and the inverter switches off for a little while. Really bad Ripple and the inverter is damaged, just like the MPPT, MPPT just much more prone to damage.
How do I know this? Been there, had that, with my first Lifepo4 DIY bank.
Batteries switching off under load, uncontrolled, very bad.
Like the idea of this if it was a permanent type of way to limit current. For instance if your massively over panneled, or under batteried, you can keep the charge rate low, yet keep your charge controllers maxed to provide amps for loads without going over a specific charge rate.
I guess it's a cost/benefit balance. Technically it's not an issue to build, but a circuit that can handle say 100A when actively limiting would cost a lot more than the 10 or 20A in these examples. I think it's a nice feature for multi pack setups, but the total limited current (of all packs) should be sized to handle the total PV-output to be 100% safe.
That's exactly what you can do with the right settings in the BMS. Just limit your Over Current Alarm or Protection to say 50A and the limiter will kick in at this point. So you can tune the charging current but still leave all your solar power available for your load.
@Off-Grid Garage oh yes, but reading some peoples comments on the design of the circuitry(I don't pretend to comprehend it) it might not have a long service life in that regard.
Now I'm wondering if that's something the smart shunt/victron network might be able to control 🤔
Magic feature, gives me the fuzzys
I got far too excited seeing that 😁
Andy si cargaras en ac coupling en vez de DC coupling no tendrias ese problema si cortan las baterias por alguna razon no quemarias tus mppt ya que cargarias desde el victron
What?
Fantastic review Andy I’m planning on acquiring a few bank of Jaki batteries your tha man, enjoy your booty🤙
Thanks Alan. I think there is still a 5% discount code on my website for these batteries...
I love it that you said "PVM" controller instead of "PWM".... happens to me all the time, because "double-u" is absolulely not intuitive for a native german 😅
Yeah, still happens... confuses the hell out of me sometime i e v w... 😁
@@OffGridGarageAustralia He! Never thought about that. The VW comes from Germany - does everyone call it a V V ??
Seri bms connect incelemesi yapabilirsiniz. 400v
Why would you design a battery with common port or with separate charge+discharge ports?
can this be bought separately? I've searched the internet, but couldn't find anything suitable
Hi Andi, ich hab ein Pace BMS gerade gelifert bekommen ( inkl. Akkupack ) und zwei seltsame Dinge pssen mir gar nicht. 1. CVL ist =Pack Overvoltage Alarm. 2. Balance Delta Cll Voltage= Alarm Zellungungleichgewicht. Das passive Balancing kann m.E. überhaupt nichts, da sogar mit nur 1,5 A Ladestrom hab ich zum Schluss 270mV Zellenungleichgewicht. Hast Du sowas mal erlebt. P16S200A-31258-1.03- das ist die Hardware in den Akkus. Gibt es hierfür einen aktiven Balancer zum Nachrüsten. Grüße nach Australien.
How would the victron react when it hits current limmit with and without data connection ?
They adapt, the MPPT will just deliver what the battery takes. No problem.
I find on my 3 JK BMS's, if I limit the in current to say, 25amps, the BMS doesn't do its job... incoming will still go to 30,40,50 etc amps. Do your JK's work to limit Amps?
No, none of the normal consumer grade BMS will have such a limiter. They will turn off completely once they hit the set over current protection. As I said, some MPPTs don't like that and can burn out.
Anyone found a bms with decent active balancer and current limiting all in one?
Ive gone jk for the active banacing but would love this feature as well
I am currently building an equivalent of the Seplos Mason. Different metal box, so the front panel arrangement is different. It has the Seplos 150A BMS and 16x290AH cells (it also has a 150A breaker - between the +ve of the cells and the BMS and a 180A bolt down ceramic ANL fuse - between the BMS and the +ve external terminal, and I will add active balancing). My inverter is the UK equivalent of the DEYE 16k Hybrid Inverter branded as Sunsynk (there are technical differences to meet local regs). It can output 12.9kWh (max) DC charge. So, at 16*3.6V that is about 200A. I will be installing a total of four of these battery packs, so let's say 50A each. Why would I want to limit the pack charge to 10A, or 20A? 0.2C of these cells is 58A. Surely I would set a higher limit at maybe 60A? Or is this current limiter something different?
The current limiter is a safety feature. It only kicks in if one of your BMS goes into over current alarm or protection. Instead of turning of the battery completely, it limits the current.
@@OffGridGarageAustralia Ah. Light bulb. Now I understand. It detects an inrush well over the normal limit, and so it chops it back a lot, allowing a bit through. What a good idea. Thanks for the reply Andy.
Great, just bought the JK BMS because it was the best BMS around! But apparently it's not the best in town anymore. 😭
It's the best for single battery packs.
You are a frankenstein twisted tester, in a good way. But l prefer you pushing the envelope of what's what then me to my battery bank (12x pylontech US5000). Surely you've got a solar dump load???
Yes, I have some dump loads...
Like# 107 - the new panels are physically mounted, this coming weekend I need to reconfigure into 4S2P with the 540 watt panels?
Let the flow of electrons start!
Physically mounted to the temporary ground array while I engineer and build the awning to mount onto Taj-Ma-Haul. Then I have to engineer and build the corresponding deck to cover the array when in motion.
So I’ll be stuck until both are completed!
Hi Andy on the neey active balancer if you have 2 battery packs in parallel and have the neey balancer in both packs do they show up in the app as individual units or do they conflict with each other Regards your fellow Aussie Rick
Same here🤔 all this information a lot to take in but necessary
Yes, they will show up as separate individual balancers. When you open the app and click on the three lines at the top left, the scan should show both. I think you can rename them there as well, so Battery1 and Battery2.
You can connect only to one at a time, so no conflict.
Andy u haven't given a link for supplying the raspberry. The breaker type power supply. If you can give the link would be gear.
All links are always under the video description or on my website: off-grid-garage.com/
@@OffGridGarageAustralia I checked the new power supply the black colour like a breaker. I couldn't find it anywhere in ur links. Before me asking I checked 😀
The JK-BMS outputs a higher voltage in the event of an overcurrent. In my case about 56.5V so the charge controller "thinks" that the battery is full and regulates the current down.
most likely, the JK-BMS disconnects itself and the charge controller increases to the charge setpoint
That's interesting to know. My Victron MPPT and Lynx Shunt were fried after an overcurrent event, my instinct was it was caused by the Seplos BMS. The last thing my CC saw was around 72v. I suggested this to Seplos who denied all knowledge and blamed it on everything but.
That is weird, the MPPT and shunt should never get destroyed when the BMS turns off the battery.
They should still see the voltage as the discharge MOSFETS are still turned on. Either wrong settings in the Seplos or a faulty Seplos, I would guess.
@@OffGridGarageAustralia It was a perfect storm. I'd limited my Mason 280 to 140A .5C, and there was a break in cloud cover at exactly the same time I turned on a 3KW load. I have 2 x Victron 250/100's with 5700W of Solar on each. Both my Lynx Distributors and my shunt died at that exact moment. One MPPT was recoverable from an 86 error, the other had to be sent back with a non recoverable 87 error. On the plus side I may now attempt to squeeze a Smart Shut inside my Lynx Shunt now that it has been fried.
@@pedromoonunit430 As long as the Lynx shunt does not show any DC Power in the Consumption tile, it is not worth the money for me. The Smart Shunt or the BVM is the better alternative at the moment.
🎉🎉🎉🎉
Hi Andy, what is ur NOC of ur solar. My solar is 545W per panel but its only giving out 420W. Could there be so much of difference. I hv a solar tracker working.
Yes, absolutely, if they are getting hot, the power output can dramatically decrease. 545W is at 25°C and full sun. That basically never occurs.
At first I was thinking what is a PVM? Then I remembered ah German, where W's are pronounced as V's. :)
Yeah, it still hounds me sometimes... 😊
Ideal for a DIY EV range extender.
👌👍
Good evening from cloudy hot València.
Hola 👋
Do you know of a 30s 108v bms
You finaly got the right cheap fuse Fpor the "not so cheap fuseholder!😇
8C here in rainy western Norway, but still 59 kWh today!
Any updates on the Lynx shunt?🤓
Yeah, that's the right fuse. even 325A is far to high for my test setup and cabling I have used.
No update on a potential update for the Lynx Shunt. I check at least once a week 😉 If they include the DC load consumption, it will be a great piece of equipment.
Andy, when you think logical this feature to limit the current is not new. This is done by the first good PWM chargers. I know this because i developed the first one for Siemens many, many years ago. It was 1989.
This is more a safety feature though not a pure PWM charger here.
i do not like a bms but this is nice
Its a cute circuit. Yah, since it only has FETs it has to PWM (pulse width modulate) the power feed into a filter (capacitor and/or inductor based circuit) which evens out the current from the PWM. This is a bit hard on the FETs, though, because the ones used in BMS's have to be cheap and are not designed to switch at high frequencies (see below). I would not trust it in general but if I had to use it I would not the set the current limit any higher than around 20% of the BMS's continuous current capability.
The issue with FETs switching that quickly is that the have to go through their linear region N times a second when switching on or switching off. So, for example, if the PWM is operating at 1000hz, the FET's linear regions are being transitioned 2000 times a second. When a FET is in its linear region, it directly dissipates the voltage difference instead of acting like a simple switch. So there are severe limits to this sort of circuit.
You could put a scope on the FET output(s) and see what PWM frequency they are using. It can be anywhere from 60hz to 1000hz for this application (is my guess). In anycase, that is why the current limiter must limit to a relatively low value. Otherwise the FETs would melt.
That's interesting. I've seen similar BMS's with power resistors and heat sinks which I assumed would be PWM or they just switch the output via the resistors until the current drops below a certain value. I always assumed that inductors on the Pace BMS's was because it was a switching buck rather than a filter for the PWM. Seems silly that they would use bunch of FET's just to get a constant current rather than dumping the output through some power resistors.... either way its burning as heat. Or is there more of an advantage to using PWM over switching through resistors?
It’s a buck converter.
@@roadeycarl You can use resistors for relatively small currents but nothing significant. Resistive circuits waste a huge amount of power and you have no real dynamic control over the amount of power you wish to allow to pass through. All that is happening is that the power dissipation is being shifted from the FETs to the resistor(s) and that might not be an improvement.
The inductor circuits are essentially buck converters, but with the very significant difference that the output is ultra-low impedance due to being connected to VBAT. Basically the output looks like a short to VBAT, and that creates additional problems.
Normally the output of a power supply is connected to a relatively high-impedance consumer, not a low-impedance consumer.
I tried compacting the explanation but honestly couldn't get it any smaller than like ten paragraphs so to make the story short lets just say that the low impedance output creates issues with component selection and tends to cause feed-back to the switching FET, potentially causing more power dissipation to occur in the FET above and beyond losses from fast PWM switching.
@@junkerzn7312 phew sounds plausible if I only understood most of it, I assume your a tech on this stuff, hats off to you🤟
Thanks for taking the time to explain, it's very interesting!
Should be in all BMS's
Yes!
One other thing to note... PWM circuits are incredibly noisy. They are like the most garbagy switching supply you can imagine. That can interfere with RF applications like WiFi and Bluetooth. I can pretty much guarantee that none of these products actually pass the certifications they claim to have if the PWM is running.
Yes to get the fastest switching you generate a lot of harmonics. Filtering is possible of cause but it should probably be in a metal case as well to avoid radiation.
Hey Andy, i don't understand your argumentation in 8:20 that disconnecting the load would destroy the solar chagers. I mean the charger intput has to withstand the open circuit voltage of your solar modules in any condition. Its not the job of the load to keep the PV voltage in an accetable range for the charger. Thats just would be a wrong dimensioning of a solar system.
Many chargers/iverters uses the battery for smoothing, and could die if you suddenly under load removed that. It has nothing to do with high PV-voltage, rather that a lot of energy is flowing. My guess is that disconnecting the battery during high amp charging could make the voltage on the battery-side spike before the output regulation can react, and damage either the charger or other equipment still connected on the battery-voltage side.
That has nothing to do with wrong dimensioning of the solar panels. The solar has to stay within the specs of the MPPT anyway, regardless. The problem is that if the battery disconnects, the voltage in the MPPT shoots up to solar Voc. Some controllers cannot handle this and burn out.
The Victron MPPTs go to absorption voltage and continue powering the load if capable if this occurs as we have tested here on the channel a while back.
@@OffGridGarageAustraliaUnfortunately i have not seen this video. You mean the output of the MPPT shoots up to solar Voc? Were the devices from a quality brand? I mean i developed industrial electronics for tirtheen years including power stages and cut-off loads are normal test scenarios. A DC-DC converter has to handle this without damaging it self and without voltage spikes outside its specification. Maybe I measure it on my victron MPPT with a oscilloscope.
@@tamazerd This is not a guess. An MPPT charger is a DC-DC converter. A current flow creates a magnetic flow in its inductor and this energy lets the voltage rise if the current cuts. For this reason you should place freewheeling diodes in parallel to relay coils etc. But such an active device has to handle this behaviour with a quick regulation path and output protection parts if necessary (TVS-Diode, VDR etc.).
@@pierreleger2709 The manuals say do *not* have PV connected without DC in place. Victron say this.
The ideal solution would be charge limited once the cells go OVP and feeds exactly in whatever the balancer amps is. This would assist balancing without slamming on and off like the JKBMS.
Well, that would mean the charge is limited to 50-100mA only. I think manufacturers should rather upgrade their balancers on these BMS.
@@OffGridGarageAustralia Consider a BMS that replaces the leads on a 5a balancer and monitors each of the cells and then has the rest.
And it would be greater than the balancer, just way less. And it still is the ideal absorption voltage. It's the maximum it can give to completely fill the cells without damaging them.
do you mean PWM? Pulse Width Modulation
yes, Yes, YES!
@@OffGridGarageAustralia You have a really good show. :)
Try that on a JK BMS
that may result in magic smoke. I have tested this once and one of the MOSFETs exploded.
It is a Buck Converter, not PWM
That is the same principal though, isn't it?
FIRST!
Congrats!!!🎉
🥇
Hilarious. Hark back to the number of times I posted on this channel in the past about limiting battery current during parallel charging to ensure no battery is exposed to excessive current as battery impedance changes during charging yet got told it had been tested and wasn't something that was necessary.
Just farkin' hilarious.
Well, as I said in the video (not sure if you have watched it), this does not occur under normal conditions at all. It is a safety measure and feature, nothing else... It has never happened in my battery shelf and these kind of balance currents do not exist in parallel setup. At least not with 3-6 batteries in parallel. When fully charged, one battery takes more current from the charger than the bank next to it. There is no reason to control the current flow.
Again, it's a pure safety feature when introducing a new battery bank.
@@OffGridGarageAustralia Current divergence happens in pretty much all battery systems and is something all commercial battery system design takes into account and mitigates in one way or another.. The only people that fight uphill to say that it doesn't are the people that have not actually performed correctly implemented tests or perhaps any tests at all.
Hell you even half admit to it in your own post just now. The penny is slowly falling towards realisation. Maybe in 5 years time it will finally hit the floor.
Andy's knowledge is continually evolving. Of course there will be gold nuggets in the comments section before Andy concludes X, Y or Z, but those nuggets are sat amongst a pile of noise. You can't expect him to collate every bit of info - he would never get to do the hands-on stuff. Don't get bitter about - please teach us more about what's done in large battery systems.
🐸🐸🐸
🐨🕷🦘
Would be better if it was like a soft starter . I mean no one wants to see/hear the spark of 100a’s in 0.001 secs !
Well, the PWM controller does that and regulates the current down from OCP to 20A/10A. This will take a second or so...
I understand it is a safety function, but setting it at 40AMPS and it works at only 20 amps is a FAILURE !
Have you tried setting at 60Amps and seeing if it is still faulty and stops at 20 Amps ???
I suspect Pace gave you this BMS for FREE
HI
Am I being stupid
You set the AMPS limit to 40Amps, but it limits it to 20AMPS ??
Are you paid by Pace, ????? by saying it works !
WHY keep saying it works ???? that is NOT working !!!
Be honest - it does NOT work !
That's not how it works, my friend. The current limiter is a safety function in each of these BMS.
🦦 aha, something learned, thx 😄
Yeah, me too...