4000A BMS?
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- Опубликовано: 20 июл 2019
- BMS - amzn.to/2XUV0U3
Contactor Relay
150A - amzn.to/2JSijUX
200A - amzn.to/2XSOAVK
300A - amzn.to/2JRAA4F
500A - amzn.to/2XWqqJI
4000A - j35.us/Gigavac-GV200PA
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There would be a lot of very confused people without you. Thanks for the channel it's one of my favourites.
Here's a little trick I use for reducing the holding current on a contactor. Hook up the contactor / relay to a power supply capable of driving it. Apply rated voltage to the contactor to close it and record the voltage across the coil and the current through it. Use R=V/I to calculate the coil's resistance. Now reduce the voltage across the coil until the contactor opens and record the current through the coil. You'll want about 130% of the current going through the coil to keep it closed. Now you have enough information to calculate the resistance and power rating for a resistor to put in series with the contactor's coil such that, once close, it will remain closed drawing just enough current to keep it closed. The trick now is to find an electrolytic capacitor to put in parallel with the resistor that will close the contactor fully when power is initially applied. Usually several hundred uF. The voltage rating of the cap need be no more than whatever the voltage drop is across the resistor. Take note of the cap's polarity as well. This can significantly reduce the power consumed by the contactor, which will also run much cooler.
Yup that is a home brew version of a constant duty solenoid driver. Best way to do it is to use a sense that indicates closure and then enables a pwm drive to the magnet. Another method is to use large IGBT bricks to switch the current on or off. No moving parts and for a simple switch they would likely outlive whatever the load is.
@@christopherleubner6633 like a coil econimizer some contactors have built in. you talking about igbt like in the bms? or or those called mosfets? your saying replace the contactor with igbt? so bms mofet turns on igbt which turn on load?
Yes. The other problem with some of those contractors is, some are not rated for continual use
yep as they are often used for just starting bursts....ALso check how many amps the coil requires, thats continuous energy required
This is exactly what I was imagining and just found you doing it. no need to test it then. I am going to do this! Thanks!
Mmmm that is nice idea....
I was looking for a high amp BMS for my project and it is very costly.
When i watched this video ,bulb lights up in my mind...so i am planning to use this idea...
Thank you for both to the person who asked the question and to Jehugracia.......😃☺👍
Awww, you look so young back then in 2014. You're so grown up now !! Time flies really fast..
Is there any way to receive a wiring diagram/more detailed wiring info of the bms to relay I will be replicating this battery maybe bigger for car audio
Jehugarcia
I just noticed that you work on high power/ current circuits without protective glasses.
Consider wearing safety glasses if you are making the connections.
You are a very talented person that loves video and photography. You need your eyes- protect them for us.
Your a great teacher.
Greg
I have exactly this issue of looking for a 300amp BMS... You just gave me a cheaper solution for my requirement. Thanks Jehu
Always like your content I had to watch this one twice cause I thought you drifted off subject at first!!! 💯🤪
For my VERY HIGH POWER systems I use IGBTs. They can be pricy but they are solid state (I mechanical switches with coils that pull power on their own). Plus if not done properly the inductave spiking or kickback will blow up your BMS so you must use a freewheel diode. IGBTs are just amazing.
A little late to the party but IGBT's are simply not the way to go, given that they have a fixed voltage drop of something around 1-2v, depending on current. So if you're passing say 100A through the IGBT, it will be dissipating 200w of heat. That's a huge loss right there.
Now of course if you're passing 400v at 100a through that IGBT, a 200w loss isn't THAT much compared to the 40kw that its switching, but it's orders of magnitude more than the 2w that a modern day 500A relay consumes to stay closed.
@@00000005547 "it will be dissipating 200w of heat" compared to the 1.5 to 2 watts of the relay coil if it has an economizer
... 7-8 watts if not.
Great vid - I love the comparison of the motor controller to the BMS to illustrate how costly a mosfet-based BMS would be. I’m slowly learning about these things because like many others I need a high-amperage BMS solution and saw the all-in-one units topping out at 300 or 400 amps.
remember everyone if your using these for alot of use you can also get a solid state relay that can be used much more
hi please answer a question: once the battery is discharged and BMS shuts down the contactor. then how does BMS Reconnect the contactor so the battery can recharge? is it applicable in a single port configuration? thank you
The BMS can sense also the "disconnected" connector.
Same question in my mind
Read the description on some of those. On the 400a, it says that's peak only. What worries me about contactors is contact welding. My 3 wheel uses some of these for reversing and I've had them bind up several times. Mileage may vary.
I have seen/heard of using a small capacitor across the contractor points to damp the arc to prevent/delay contact welding. Electrical engineers on this group may want to verify this.
I was thinking about doing something similar for my power wall
how would i go about making a jump pack with these batteries?
Hi Jehu, how long have you been able to get these relays running in your current (parallel) setup?
The only difference in between this setup and doing a car audio setup would be you need to add a big fuse somewhere in line right after the relay... it's not a contactor it's a relay that's all it is. They make those relays super strong and if they're not enough you just use more of them to spread the load out... on hydraulic cars they use a bunch of them.
On the subject of main contactor parasitic power loss, the voltage required to hold on a contactor is much less than what is required to close it. This is because the armature gap is practically zero when closed and requires less emf to hold it closed. If a manual reset circuit is needed, a simple "hold-on" circuit can be used with a voltage divider resistor in series with the contactor coil to provide 75% of coil's rated voltage with a momentary switch providing the start-up voltage.
that reduces the pressure on the contacts, which reduces how much current they can safely handle. When your switching such large loads the current draw of the relay\contactor is basically meaningless. The only time it becomes meaningful is when you leave it on all the time while your NOT using it. Or possibly if your using a large bank at a low load such as in a Camper or RV.
This channel gives us DIYers options to do the samething in a cheaper way..
What are the implications for charging? Especially charging/discharging are on a common pathway?
Need a latching relay if it could be made to work with the bms
So BMS is just a simple board that watches cells voltage and sends a signal to shut the circuit on or off. All it matters is the power of the relay.
Not talking about balancing of course. I would do that couple time a year with a decent balancer separately.
A simple RC hobby battery monitor is like 2$, which sends a signal if any cell being too low or too high and capacity or power of the battery doesn't matter. The signal can be translated into a relay switch then.
Again, why BMS are so expensive and complex? All you need is a decent voltmeter for each cell and a simple logic to send a signal to a relay/contactor.
Some BMS systems try to balance the batteries. They try to discharge the ones with the highest voltage so that all of them are in a specific voltage range. Others try to charge the batteries with the smallest voltage by discharging the fuller ones. And there are the simple ones which simply monitor the voltage of each battery and then send a signal if one of them is too low.
For motor control they are called contactors, Automation Direct has 360A with 24V coils. In cars they are most commonly called solenoids, starter solenoid, and is used to turn the starter motor to crank the engine and rated 100A peak in cars.
If your searching for a super high amperage contractor most engineers will use 4kA not 4000A. Higher amperage units usually require a lot of clearance and sometimes external lines like cooling for an arc welder.
Hmmm you could use an old robotic arc welder to switch 1000s of amps.
In 6kwh 20s and 12p battery pack which BMS will be good to use
How do the typical "12v" relays transfer over when you UP the voltage. IE how will a 300a 12v relay work on a 72v system? What relays to you use for typical higher voltage Ebike builds?
Ok cool. So 2 ?s please. 1: does that work in reverse for charging current( i have 2 300 amp alternators) or is that still controlled by the current rating on the bms. And 2: What is a display(like the one you show) that can show 12v and up to a 1000amps of draw without using an oldschool amp meter being thats kinda annoying to wire into the dash and only shows current lol. Please help. Also could you wire supercapacitors in parallel with this without an issue, just out of curiosity.
I wasn't aware that ev conversions didn't use a bms? Any video or way to get more information on that? How does charging work on larger ev packs
Is this for battery amperage size i.e. 24v 400A ??? Or for current charging ability 400A/hour ????
Could u be specific thanks
I have had trouble connecting relays to BMS this way. Most of those BMS switch the charge and discharge current independently. So in the configuration shown in this video, the relay will stop over-discharge but will not stop over-charge. If you flip the current flow the other way through the relay and BMS, it will top over-charge but not over discharge.
I have coming to me 32 cells Lithium 66160h Titanate 2.4 40Ah with 2 BMS’s and I saw the video you did about not really needing a BMS I Got it because in some of you’re videos you are wiring them up - this is for my home emergency battery back up what would you say is the best way tio wire it up 76v I have ?
Hi, do i use common or separate type BMS for ebike (72v 20s 3p 80A continuous, 18650 battery)
Thx
Is this setup still going to balance the cells though or does doing it this way just provide under/over voltage protection?
I count 32 cells and he said 4 cell BMS. The BMS might be balancing the 8 cell pack to a degree but this looks like a high/low voltage cut off. I am only guessing. What do you think?
Def need to install this in my car audio set up. Winter is coming around and when it's too cold to use my lithium I don't want to have to unplug it till it warms up lol, only bad thing is the relay is a choke point and another drain but eh, there is so much parasitic crap hooked up already. Beats pulling wires when it's cold
don't they make a over under relay switch? Basically sensing the voltage and turning off once it reaches certain point that you said
How do you run 2 separate voltages in your car? Eg. 16v and 12v
Keep them on separate circuits, or use a DC-DC converter to step up or down.
Should you mix agm and LTO Ying Long . I have a car audio system with an amp that can do 7800 watts burped, for an everyday music about 4800 watts. Should I go all LTO and zero out agm?
Agm is a super waste of money LTO can last well over 10000 charges.... seriously will have them for the rest of your life
what do you think of t LCB (Lithium Ceramic Battery )
I would like to make a battery for my boat 24v et 12v de 140ah ?
is it possible to have both voltage on the same battery
without unbalancing the whole?
Hi.... you forgot to tell us how you wired the bms to relay circuit........i.e where do i connect the relay control voltage on the BMS board? thanks
Does anyone know if those TC connectivity Contactors are rated for continuous duty?
agreed some car solenoids are starter activated only for 3 seconds ... melt down soon after?
Hello, can I still use this type of BMS if I charge above a 100 amps? Reason I asked, is because it says it has over charge current protection of a 100a. I have a 320a HO alternator. I want protection for temp/voltage ect. any recommendations?
How about using a MCB controlled by a servo?
Jehu couldnt you just break down the number of cells in your battery pack to like a group of 8 or 12 or 16 or whatever and then use a BMS without the relay. And then parallel the groups together each with the own BMS ? Thus getting rid of the need for the car relay ? And still have 12 volts ?
well this is all good when battery is balanced, but how do you balance a big battery like that "throw a wrench at you" and go out of balance for no apparent reason other than slighyly smaller capacity and many charge/discharge cycles?
Did you look at igbt?
Hello
thank you for this useful video
please i have question , if i have 23S BMS , and i want to use 2*23 BMS to controle 144v system 400Ah using this method. is it ok and safe? and what about balancing the cells in charging and discharging?
thank you
awsome video, great info. can I use the same idea to charge calb batteries? I have 100ah per cell and the same bms. but the charge rate is only 10amps. I have a Prosine 3.0 that can handle charging better and has the correct cutoff setups. any concerns or cautions?
Yes
@7:21 can you show the build where you paralleled this BMS?
Thanks man, Your Awesome.
You should build a MOSFET BMS . It would be really cool to see you do it.
I make a lithium battery just like that with 32 headway cells but I wired it with a 60A 4s bms but that bms shut off the battery at about 12.4 volt but I'm wondering what kind of bms is best to used on it that doesn't require saudering because I get a 100amp bms from Amazon that is going giving me hell to Sauder the main terminal leads..
If it's for mobile audio, the BMS can just control the remote-on of the amplifiers.
Correct.
No, nice in theory but in reality, the BMS is there to protect the battery bank, in fault, amps and other loads can still draw power. Use a breaker.
contactors in parallel do not operate at identical times. therfore under high current fault conditions the one that opens first will suffer severe arching and will weld closed in the future.
Except I’m been running parallel contractors on my diy ev for 10 years now despite people like saying it wouldn’t work
I think Perfect for a golf cart battery!! So, charge through BMS directly?!? Use a Golf cart solenoid to apply power to the motor. They are $15 on Amazon. So, thinking of a 12S Lifepo4, which should charge at 20A. Wonder if BMS's have variable cutoff voltage. Thinking to cut off high speed at slightly higher volttage (2.4V?) and low speed at 2.2V? So if battery gets low a long way from charging station, can limp home at low speed..... Would this work?
on a system like a powerwall you could use a latching relay instead of a relay that requires constant power to stay on.
Thomas Kelly - I've been looking, but latching relays that powerful seem very expensive. Do you have a source for cheaper ones?
Why would you interrupt high current instead of telling the load or charger to shut off?
Because your load is dumb
Im building 4, 64ah batteries, I bought the bus boards from you but now...what would you recommend for a balancer, temp/voltage protection? also looking for a cell monitor like you have, I know it's discontinued, so should I get a battery go monitor? I'm new to this stuff so my head hurts from all the research. Can I just paypal you for Q&A's. lol... Ugh! thats how I feel .
I have a big question made a battery pack but I can't figure out what it will handle I have a pack that has 3s 12p I have 2 of them 72 battery pouches in total the batteries are 9 years old but still hold full charge and capacity found at 3.75v and above brand new out of the box from a warehouse
I am planning to series 8 packs of 7s20p battery for use on a 6KVA 192VDC online UPS. Can i safely series 8 7s bms at that voltage? Or is there a better way to set this up?
Yes you can, but as you increase voltage it becomes less safe to any humans that might get in the way.
Sir we r making a high speed car ...we r making 80kw of battery with 400v
We r dividing whole battery in 4 part each of part has 100v and 200A ..sir which typ of BMS we should use ?? ...any suggestions of bms master and slave bms ?? Or any other
Just wondered why you have the negative wire from your XT60 under your last cell bank at 5:30 / 10:13 time
Look for solid state contactors. They use small fraction of the energy a typical contactor uses.
Solid state relays a basically resistors that allow current to pass when a voltage is applied to the gate terminal.
There is a residual resistance that is much greater that what the relay coil has.
SSRs tend to be good for low currents or when switching needs to be very quick (i.e. PWM)
Otherwise electromagnetic relays can be much more efficient ... but be sure it is rated for continuous duty.
What kind of current shunt are you use for measruring current of 200amps
Hey man I have a question and your the only person I think can give me a really good answer. I wanna run two different voltages in car. I want one of my batteries; the front one; to charge to 12v and I have a bank of 40 headaway battery cells that I want to charge to 16v. What can I use to charge my front battery to only 12v so that I dont fry my electronics? Also i have a 240 amp alternator which is externally regulated.
It uses hall effect sensor to measure current
@@joshmesser1165 Two alternators possible?
@@niceguy100000 no one alt
You have removed short circuit and overcurrent protection from your bms?
Over current can be handled by the drok meter
Please add a circuit diagram so that it's easy . I am having the same issue please help
Thanks for the help and the name drop.. ( points with my son he loves you tube).. I still have more questions.. the bms switches on the ground so I can hook the relay to a key power and it will shut off when my car is off to prevent discharge?? Also can I run constant power to the charge part of the bms to balance the cells when the car is off??
4:20 That's a Ford starter solenoid if you want to buy one local and for cheaper.
How Wild is it I was looking at the differences between relays solenoids and contactors last night
Contactors are like a woman , there all good but better ones generally are way better . . . Lol .
How about overcurrent protection? This won't help it right?
Use a fuse
Hello i am very happy to see a high amp on youtube
You should just get the SBMS from electrodacus. It allows direct connection to the battery and allows you to turn off the loads via a small DC SSR.
Actually this technique would allow the same. An SSR could be used as a contactor but I would suggest something more powerful. On the other hand Dacian is brilliant. Have you seen his build process?
Remember i said in your last live stream, i can't order batteries for my E-bike, so i had to order here from Norwway, but only a 816Wh battery :( which should only get my about 34 miles (54km) of range, wanted a bigger one, but as soon as i get all the parts, i will send you a picture of the ebike, then you can see for yourself, might make a video for you aswell
Does it use 18650 or another type of battery?
I always called those Solenoids.. I guess I've been wrong big chunk of my life. 🤔
I use those in car audio to charge a second battery only when the engine is running. Once I killed the ignition it breaks the circuit no more current flows to the secondary battery so it sorta isolated it from the main car battery.
Solenoid is also correct. Americans always choose the simplest word to describe something!
Most people use these interchangeably. I always think of a solenoid as moving something mechanical, like a starter solenoid or the valve in a dishwasher or washing machine.
I understand if you're not paying attention it could be a safety issue, but why does the BMS also need to be able to break the entire load current if you have an accessible shutoff switch? All you strictly need still is cell voltage monitoring, but just hook the alarm up to a buzzer not the whole pack. That way you might be able to pull over more safely etc before totally disabling your drive system, in the case of a car. A few more seconds at low load won't bring a cell that just passed 3v to zero.
Hi Jehu I tried to buy the 'DIY Lithium Batteries: How to Build Your Own Battery Packs', in the UK from Foyles book shop, they tell me the US has placed restrictions; I cannot purchase hard copies in UK, this may be the case for other countries too. Chud
I contacted my local library and they requested it for me. Cost me 50p and I had the book a month later.... Plus now lots of people can enjoy it at the local library
I bought an 14s bms, but i did not run the main current through it, instead i run the negative straight to the charger and inverter. I figgured, it is particular bad for the charger to get disconnected from the load/battery. And I found out, that the inverter has its own cut off voltage shut down setting. Its a grid type inverter, and it can comeback on when the voltage is up again. oi I just connected 15 little wires to the bms to run the equalization procedure, and left the thick negative connections unused. works like a charm.
If you need that many amps you could get smaller cells grouped in banks of 12P or larger and use an active balancer, or 60P with 1S balancers. BMS devices really aren't meant for heavy lifting and placing them in series is a bad idea IMO. Now you introduce relays as well as the BMS increasing the wiring complexity, adding yet another potential point of failure and then additional size/bulk to your battery if you're trying to make it portable.
Keep in mind also that just because a cell can output super high amps it doesn't make it a smart idea to do so. These Headway cells are proprietary and were specifically made for a certain application (maybe you can enlighten us on their origin!!!). Sure, you could string 16 of these together for a 48V 200A pack, but your 48V PSW inverter won't be running for very long LOL, and expecting to drain each cell at it's max rate won't bode well for the cell's life span either. It's also a great recipe for FIRE if you're not careful.
If I was building with these cells I'd string 8 together in series, wire in a 60A 24 to 12 volt DC-DC converter and split that output to three 12V 20A cigarette lighter plugs. Now you have a compact portable pack you can keep in a bag in the trunk of your car to run tire inflators, charge devices over 12V and with a small 300W inverter give you enough AC power to run a laptop.
All is true but he was talking about using in a car for car audio. In some cases like me i have 2 300amp alts and somewhere around a 400 amp of constant draw and 8 to 1000amps of peak burst draw and thats why he went this route. Otherwise i would agree. Not really a setup to use with an inverter true. Unless it can handle it and you need it i suppose.
@@demolishedmembrane Got it. I'm not familiar with dual alternator set ups in cars. I've had two batteries connected to a single alternator and it would just charge slower. I am assuming in this case each alternator is charging a separate battery, but the batteries aren't connected together.
@@Luscious3174 in my case actually all wired in parallel including 7 batteries lol crazy shit but alot of car audio guys have this and more. Thats why i was watching this to see if it will work
Great video
Your link doesn't work for the batteries
Wow awesome 👍
what is the device on the left at 6:00?
Search for Ming HE wireless power monitor and you'll find it. There are different versions for different voltage/current requirements.
Latching Relays. The stay either open or closed without continually drawing current. They have high current ones for RVs. That's what I use.
Do they exist? I’ve never found ones I could order and try out
@@jehugarcia P.S. You do amazing work.
@@jehugarcia www.digikey.com/product-detail/en/te-connectivity-potter-brumfield-relays/1-1414939-4/PB1315-ND/3318141
260 Amp contact rating. 12 volt Switching Voltage.
@@jehugarcia Dual coil means you have two different inputs to switch the relay on or off. Apply power to one set of contacts to turn on and another set to turn off.
Single coil means you have to reverse the polarity of the charge you are applying to the one set of coil contacts to switch it on or off.
You Rock! Thank you
How To BMS a 1000A Continuous Battery Discharge
Just use the BMS and have the P- connected to the coil on a Contactor. When LVC is tripped the P- will no longer send current to the Contactor coil and the Contactor will open and disconnect the battery from the motor controller. Then connect your load direct to the battery B- and B+ (of course using a fuse, a pre-charge switch circuit to pre-charge the load if needed, and an Contactor switch where the coil is connected to the P- of the BMS).
Also the Chargery BMS24T has a 600A model that I think will do 300A continuous and is only $320USD shipping in.
Use Mosfet relay with optical insulation so it drain maybe 1mah per hour or MAKE YOUR OWN RELAY using motor and arduino....when bms aply voltage motor turn the switch on but turn motor off after that ....when bms turn off the power arduino start motor again so it turn switch off and then the motor.
So there is no power drain in the system all the time :)
Hey jehu build power wall PCB for 21700
Tent on top of a battery.
I designed mine if you are interested.
@@conceptor Pics or it didn't happen.
too smart idea
i use mosfet :D
My battery is 100 volts and 48 amps with 30q batteries with four banks of 30 cells and I can't find a bms for it :( anyone got a link?
Jehu i am the first viewer of this video, can you answer my question? Since the last one was not. What do you suggest i use for 30pcs battery pack to use with solar panel? How do i charge them? And balance them? What hardware do i need?
@@NicolaCasetti thanks for prompt reply. I dont need invertor. I am going to use the system on DC with 7 pcs of 1W LED BULB. My biggest challenge is how to wire BMS and also include a digit meter control on the system (Battery Monitoring System).
I have watched this video and the video where you put 2 BMSs in series. I have 45 (3.2v) lithium iron phosphate cells making up a 144v battery pack. i am asking can I manage all the cell with two 24s BMSs connected in series but not connected to the battery pack for charge and discharging. (use them as switches as demonstrated in video) Run 12volts through them to a solenoid contact-er that will turn off the charger when max voltage is reached per any one cell. If yes, I intend on adding a two way switch on dash. Up for charge and down for discharge. On discharge BMS will interrupt 12v to main contact-er for low voltage shut-off. Thank you, Love your videos!
What about if you want to run 4 of theses batteries on car audio ? does each battery need its own bms ? How do you wire that ?
48v ? Get a 48v bms
@@jehugarcia I want to keep it at 12 volts
@@mrmagic3067 48 V to 12V converter .
Can you not just use a small relay to turn inverter off?
A small relay would not handle the current and would burn up or weld the contacts. A contactor is ideal as it is design to switch large current loads.
htmagic but the relay wouldn’t be switching a large current if it was just turning the inverter off. Would it?
The switch on the side of my inverter does not look like it’s rated for anything special. I would of thought it just stops the mosfets within the inverter from doing there thing.
Is that not right?
Would it not work similarly to “niceguy100000” comment about the remote on on a audio amp?
Yep this is what i do with my victron inverters.
You can find a normally close contactor....then the coil is activated less time?
Cool
I even make my own plates out of aluminum sheet cause you're out of stock on those plate on your website
No way that one in the picture would be 4kA that contactor would be good for maybe a few hundred amps. Use a similar but bigger one with a field sustain mode for a solar inverter to enable it.
A solid State Relay does not have the High Current issues.