Small BMS Vs Large BMS

[@lee-johnson]

In HVAC, using a small controller to switch a large contactor is normal. Done all the time to save cost. I would love to see the thermal camera on this setup.

[@angusfreeman]

In HVAC, what is the worst case scenario if the contactor fails closed? I'm planning on using this method also, but don't feel it offers 100% protection since you can't completely trust the contactor.

[@scottleggejr]

@@angusfreeman Depends on if the contactor is normally closed or open in your design. The coil can sometimes burn out and the latching charge for the coil is wasted energy, but likely a hell of a lot less than a giant MOSFET.

[@jakeandrules7724]

Can use 2 contactors in series, as a double redundancy, but like mentioned here, that coil does use up some power to hold the contacts in. Depends on the contactor though, might be worth it.

[@SerendipitySue]

please use a tripod... I was getting seasick watching this video ;-)

[@maddeusdoggeus1]

😂🤣.....😊🙂......😐😯......🤢🤮🤮🤮🤮🤮

[@malk6277]

Camera work is making me crazy!

[@positronium3525]

I have a 100A Smart Battery Protect so unless Victron updated their hardware since I bought mine, the thing with the battery protect is that the DC Solid State Relay is meant to allow current in one direction. You can't flow discharge and charge currents through same Battery Protect. The SSR is meant to have the current flowing one direction (most commonly discharging battery) and charging the battery causes the relay to overheat and possibly destroy it. I advise to look at the wiring diagram of the battery protect manual to ensure that it can be used safely for charge and discharge applications.

[@jehugarcia]

Then it’s worthless

[@nebulight]

jehugarcia not worthless if you use it how it’s designed. It’s meant for discharge protection not as a switch. You can use a charge protection too but you have to have a second unit. I have two in my camper van. One for my dc loads (not the inverter) and one for my charge sources (solar and dc-dc).

[@jehugarcia]

That’s makes it a really expensive weak one way switch..... useless for my application

[@nebulight]

jehugarcia correct useless for your application. But as the name suggests it’s a battery protect not a switch. ;) Just control a contactor with a precharge circuit to protect the contactor and inverter. Take the hit on current draw as it will be minimal compared to your incoming solar charge.

[@coryfrey5040]

Also, if you check the data sheet it has a max operating voltage of 35v. It is not intended for your application at all.

[@joshuacribb2523]

Hey Jehugarcia, be careful recommending the use of high voltages through a low voltage 12/24v contactor, even though they are solid-state going over the voltage rating will cause the MOSFET to deteriorate or worst case blowup which is expensive if not dangerous. Same goes for mechanical contactors, they can fuse closed (on) when over volted.

[@janbuijs4868]

It's the amperage that you should look at when you say it's not going to electrocute you. Not the voltage ;)

[@jehugarcia]

My skin is not conductive at low voltage so the Amps don’t matter in this instance

[@jakeandrules7724]

Lol! Higher voltage followed by amperage is what you need to watch out for. You need to learn a fair bit more before commenting.

[@randal_gibbons]

@@jakeandrules7724 that's probably why we don't see signs that say "Warning High Amperage!"

[@earnwithbots2783]

Can we get the link for that black power supply the 48 volt one I mean?

[@payton1284]

Wish I had seen this before buying a 7s 150amp daly bms

[@joevasquez1776]

To support the voiceless, I can no longer use the like button ✅ . So here is a written like.

[@farnsworth9350]

SS relay is terribly inefficient, HVAC compressor relay is cheap and more efficient.

[@MrPhatties]

*Contactor

[@positronium3525]

SSRs have extremely low current draw usually a couple of mA. I know automotive relays are around 100 mA. So the current draw for SSR is about 20-50 times less than a comparable automotive relay. The only downsides to SSR I see are some DC SSRs only allow current in one direction and SSR typically require heat sinks as the thermal conductivity of semiconductor component is not as high as metal.

[@peterg.8245]

Why would a mechanical relay be more efficient than mosfets with no moving parts?!?

[@tomstdenis]

@@peterg.8245 MOSFETs aren't resistance free. Even a [say] 4 mOhm drop over 200 amps is 0.8 volt drop (160 Watts). That's why the Victron Energy switch is a giant heatsink.

[@jakeandrules7724]

I like the idea of using a shunt trip breaker to break the connection of the battery bank and solar charger at the same time. It would be the most efficient solution as the only power wasted in heat or power, is the power supplied to the shunt for that fraction of a second to trip that breaker.

[@KarlMiller]

OMG! You are all over the place. What the heck are trying to do?

[@noelopez2576]

Mission, Texas 1.06am Hurricane Hanna don't stop me watching Jehu's updates 😎👍

[@VIPK9]

Also in the RGV its flooded here

[@grenebulax]

In corpus.. didn't hit here so bad, but still a lot of damage to the marinas

[@epianguiano7880]

Mercedes texas here. Noe have you built any of the Jehus DIYs?

[@noelopez2576]

@@epianguiano7880 yes the kits with the bms boards but not installed in anything yet. Haven't messed with 24v in anything. Only 12v system in my shed with Harbor Freight panels.

[@herbertvonsauerkrautunterh2513]

You move the camera and move around too much.. I can't watch this

[@cameronblackmon9540]

This is the same principle the SBMS by Electrodaucus operates on

[@ronriley3752]

I am a retired electrical engineer. It would be a god idea to do this stuff on a non conductive, non combustible surface. In my house and workshop, I charge most computers, phones and pretty much everything on cement board, ceramic tiles, porcelain. About ten years or so ago, I had a 40 Ah battery pack go exothermic. It was on an end table with slate inlays, and that saved my house.

[@rhysemerson742]

I realize it is kinda randomly asking but do anyone know a good website to stream newly released series online?

[@kasonthaddeus4871]

@Rhys Emerson I watch on flixzone. Just google for it =)

[@atlasleonel7616]

@Kason Thaddeus yea, been watching on flixzone for months myself =)

[@rhysemerson742]

@Kason Thaddeus Thank you, signed up and it seems like they got a lot of movies there =) I appreciate it!!

[@Snuk1s]

What about the balancing current? I suspect that higher capacity cells need higher balancing current.

[@jehugarcia]

No

[@2Cineman]

@@jehugarcia please explain why no, unless your not bothering to allow the BMS to ballance the pack, by never doing complete power cycles.These BMS's are designed for relitivly low Ah high current packs Ebike etc not powerwall storage capacities. They can only bleed off 100-200mA at best that would take a few days to have an impact on a 100Ah battery. it would also require a low current float charge for a long peroid to work propperly in order to bring up the less charged cells. Float charging lithium is a bad idea, you get dedrites growing accros the plates which will short out the cell in the long run.

[@ripsta2009]

@@2Cineman no they do not need a higher current. Batteries honestly shouldn't need balancers to stay balanced. The balancers are only a maintenance thing really. If you have to have a balancer to keep the batteries at balanced voltage then you have some cells of different healths and a balancer will not be able to keep up with the balancers. Batteries should stay within 10-20 millivolts of each other without a balancer. Usually within 10 millivolts. And then the balancer will finish the balancing.

[@martehoudesheldt5885]

get a cc-cv welder and get some current.

[@kingcardano2.9millionada24]

Don't ever trust any Chinese electronics lol ever because everytime is the first time lol

[@tedco-Theo]

hELLO ! Please, is it necessary (and why) to put a "victron energy battery protect" 🙂😮😮 like I got a good BMS on my battery ? It seems to do a similar job, no ? Thank you. (perhaps have you got also a better idea. Thanks)

[@alsvideos4110]

I enjoy the show

[@johnwinchester7472]

will you be doing testing on the 7S Daly BMS, iv'e been thinking about getting 1 for a while now

[@tommywakefield08]

Bro thanks soooo much for this timely update I’m literally trying to find some big bms options for my electric quad. Please check it out. I’d love to hear your input. This project wouldn’t be possible without your videos.

[@tommywakefield08]

kzbin.info/www/bejne/qZqbcmmeZb-JoZI

[@wantafastz28]

Sense kind of sucks.... @jehu. You should check out brultech for your shop if you are going to have multiple projects going on....vastly superior.

[@chefbperez]

I saw the lifepo batteries on your site I'd love to build a 24v battery for solar. Pero me confundes mano!!!! Nervous about investing in this endeavor because I'm not sure if I can follow u clearly enough to follow.🤷🏽‍♀️🤦🏽‍♀️

[@Dorsetwatersofteners]

If you are testing please also try a solid state relay/contactor. A lot cheaper.

[@jehugarcia]

Which ones in specific? I need at least 150A

[@2Cineman]

@@jehugarcia an HVAC solid state contactor is intended for AC at mains voltages is it not?, won't work on low voltag DC Also that blue unit is meant for 12/24V battery dissconnect it will have 30V mosfets in it, on any higher voltage you risk blowing it up particularly if you have an inductive load like a motor. Also the BMS has two modes of battery dissconnect Charging and disscharging, each relies on the current flowing i a different direction, the blue bat dissconnect would only supply current through the link in one direction so youd only have over discharge or charge protection not both, either way not a good idea.

[@jehugarcia]

Yup that thing won’t work

[@akisakis9397]

hello i make electric scooter i use lipo 48v 13s lipo battery with daly bms when to connect charger 48v 5A to the battery can not charge can you help me ?

[@evlnxr]

Are you going 36v based system now? In the original video you were going for 72v. What inverter setup do you think you will use? I've got a big store of 36v battery packs from scooters, 30 cell, trying to work out how the grid tie setup works.

[@scottleggejr]

In your example @ 7:53, you need a separate port BMS otherwise, when you hit low voltage cutoff, your charger will never engage again without manual override.

[@scoty_b80]

was going to do same with victron relay but can't charge battery though relay so won't work for me 👎👎

[@drgloverable]

With all those Daly BMS - it would be great to create a review of them, and also instructions showing how to do, eg parameter adjustment, low temp cutoff, SoC charge shutoff etc using the Sinowealth software tool. Seems these are popular, but with not a great amount of useful information.

[@paulkosmos2426]

crazy but not stupid. :D

[@tomstdenis]

I would check what the max voltage through the Victron Energy switch is.... the IGBTs/etc inside might not handle 40+ volts.

[@benverdel3073]

The operating voltage of the bp 220 is 6-35V with autosensing 12 or 24V batteries.

[@htmagic]

Jehu,I've used solid states switches to switch high current for an electric heater element for a still. The solid state switch needs a 12 - 24V input to switch the output.

[@jehugarcia]

Ok..... not sure what that means

[@htmagic]

@@jehugarcia Just like a relay. 12-24V on the coil or input to solid state switch (SSW), then the contacts or output of SSW to turn on or off the load.

[@roqm1248]

Info on that 48v charger

[@americannumber2]

I appreciate cheap Chinese products because they allow me to start my project easily

[@slade111111]

Чвай, чвай, да ты нормально по русски скажи!

[@marccohen5579]

You video's are very interesting buy would be better if you hold the camera still. you are getting me sick.

[@IndependentNewsMedia]

Please can you go through the setup of the Hall Effect amp meter, and its different functions. Looking forward to the Big Bertha BMS video, keep up the good work.

[@Alex-je6od]

Using that exact 7S BMS on my battery box. Works fine, seems to keep things balanced ok. Much better than the Victron whoo-whoo BMS that doesn't charge :-)

[@pulesjet]

Yep, it would had been good if all my gear would accept 36v . I had to break down all the modules and make them all 40P x 7S. I should buy another set to do 6S for my Nissan Modules. Going to take me a bit of time. Testing and configuring.

[@koh9894]

we want to see a video of cheap chinese stuff blowing up :)

[@jasondevine6014]

I just cooked a set of batteries protected by a Daly BMS. The charge controller shorted closed and the BMS saw the full panel voltage of 90v for a 24v system. When it turned the battery off due to 100 SOC, it pumped full solar voltage onto the fet shirting the charge FETs. Batteries died. Make sure you check max voltage handling of the solid state switched against possible input voltage failures, or use mechanical switch.

[@jakeandrules7724]

What charge controller were you using?

[@jasondevine6014]

@@jakeandrules7724 esmart. But point is any can fail.

[@jakeandrules7724]

True

[@jasondevine6014]

And here is a video about. kzbin.info/www/bejne/gJPRd6yLbJ6BnJI

[@mrgreenswelding2853]

That's a great idea to use a relay to increase amperage output.

[@yakz9885]

The ant bms is the only cheap Chinese bms I'll ever trust and use

[@rikilshah]

I think most of the good quality Chinese BMS use Hycon Chips, Taiwan and they all have almost similar design. So if you read Hycon on BMS, it might be okay to trust them.

[@ameoba32]

ant bms is awesome, especially with bluetooth app which gives tons of battery health in real time. I am using one for ebike and never been happier.

[@harrrytoool1391]

Not available in UK. Electrodacus is much better and there is a complete monitoring of the features. Highly recommended. Customer service from Dacian is second to none.

[@johnq8792]

very nice video and educational

[@arkangel8709]

Listen, my friend, I know you go over everything really good, with people who Watch you're channel. I Also, know that these are the same battery's that is used in The Tesla car, but I like useing something a little bit less likely to be a problem. My way of thinking about it, is this: If you have 100 or 1000 18650's verses, what would be the equivalent, "VOLTAGE & capacity" In models of battery's from Say" one of the hybrid cars, like maybe what I have been working with which is The high voltage battery models from the hybrid prius c. Each model is around 7.3 to 7.5 volts. So, two (2) Would make 14.1volts which, is just about exactly what a car alternater puts out to recharge the battery with. So, less is better, is the old saying" that works for me, cause after I've wired them up to double the voltage UNTILL I'm getting the volts, I need or want" I keep it around 14 to 28 volts, that's only 2 to 4 modules, wired in series, then if I want more amps,?? I can add more, modules.... In unison, adding more & more amps,.!!! But after ALL IS SIAD & DONE, I still only have a fraction of the number of battery modules.!!! So, my point here is this, if you have to add 50 to 150 (18650's to my 15 to 24, battery modules),... Then you have, A Whole lot more batteries and that is a WHOLE - LOT - MORE POTENTIAL, PROBLEMS.!!

[@magnusblomqvist4571]

Use Shelly EM to measure energy use. It's inexpensive but it works great. Take a look at: shop.shelly.cloud/shelly-em-50a-clamp-wifi-smart-home-automation-1#141

[@angusfreeman]

On the second PS and CC/CV on the right...is that a buck converter, or another boost converter with a slightly different design? You mentioned lowering the output, but wasn't sure if you did it at the power supply or the converter. Thanks! -- and...let us know if you find a source for converters than can do more than 20A! :)

[@sams5803]

Man I wanted to build and e-bike so bad but now I want to build a powerwall because of you

[@zoleeeagle9339]

Funny :)

[@rlsoriano]

What's a good charger for these scooter batteries?

[@MiguelGONZALEZ-qm6ke]

Yes I know better then that , it happen to me

[@MrPhatties]

Would the smaller BMS have an issue balance charging the cells?

[@kschleic9053]

The charge current should be low enough for balancing. The bigger concern is that the BMS boards have their current sensors on the B- B+ lines, repurposing those for controlling a relay will mean no current readings.

[@positronium3525]

@@kschleic9053 that is true but the battery protect is always ment to be used with a fuse or circuit breaker.

[@mkannemeyer]

Hi Dumb question (forgive me I'm still learning) : The blue device that you use as a switch, is that to cut power from the charger to prevent over charging or is it to cut power to the load to prevent over discharge? Thanks Mike

[@robertnorrell9073]

this is good advice . TY

[@chuxxsss]

I need to catch up on your vlogs. Been build a small cnc to do cct boards. Stay safe love your work. Where is your dog?

[@theonlywoody2shoes]

The Victron BP220 (12/24V) has over voltage protection that triggers at 16/32V - it auto detects which range to use based on the applied voltage. Since it controls the positive battery output you would need to “float” the 0V/ground feed to the BP220 by +8 to +10V to it or it will just trip. Victron do have dedicated 48V battery protect modules, but these are only rated up to 100A.

[@l.3626]

I love your channel and videos

[@swolath]

i use a small bms to allow power to goto my relays, ac charger for batterys when exporting enough power to the grid or gtil on when i want power from my batterys,so if bms is not happy nothing turns on.

[@josephramdhoon4167]

Hey Bro! Is it possible for you to get pictures of the internal parts of the 24V Giandel 4000W Heavy Duty Inverter?

[@sams5803]

3am North Dakota lol

[@brony4life1982]

What do you recommend for a 12 volt system for a good suplay? I have a lot of lefotver 18650's though they are dif on the AH so of courseI'd use the same, I just want something with a little more beef for higher voltage stuff other than my phone and tablet.

[@jehugarcia]

I don’t like 12v systems, I don’t recommend them

[@andrewborntrager7909]

Should you have top balanced them all together before charging?

[@swormser865]

Is the original built in bms work?

[@jehugarcia]

I wouldn’t be looking at external ones if they did

[@swormser865]

True but thought someone said they working on it before?

[@jehugarcia]

They are but I’m building this now not later

[@LarsDahlin]

Finally you got me as a new subscriber. Great work on your channel! 👌

[@rafalgwizdala8322]

Aren't you disabling BMS overcurrent protection and short circuit detection when you bypass the BMS and use it only for controlling the big relay?

[@tomstdenis]

Yes. That's why it's a bad idea. It's also just more complicated and likely to go wrong. Just buy a big enough BMS (or pair of BMSes) for the job.

[@TRICHOMETRIST]

Time for a metal table!! When 18650s gas off I didnt see a flame , heavy sweet smoke! I think the wire burns not the lithium!! Yeah some cheap crap from China can start a fire those cheap vape pens come with the flimsiest chargers I've seen them melt several times Alot if China stuff does not have that electrical code rules sticker thingy!! I got 60 scooter batteries and I got swamped !! Gotta get Bms Chargers Snot welder 😎 I like those long LG packs you(scooter?) got in your website!! Gotta grab a few!!

[@888marin888]

can i throw "any" Amp amount to my batteries while charging and they are just going to use what they want/need knowing that their max charging is 2.5A (2600mAh battery) ?

[@PablumMcDump]

No. Current limiting is essential in charging lithium ion batteries. They have a low internal resistance which lowers as they get warm, which would result in thermal runaway without current limiting as current increases in a circuit as resistance drops. More current, more heat, lower resistance, more current, more heat, POP!

[@888marin888]

@@PablumMcDump Thank you for your answer, i've seen videos where Jehu seems to throw "some" amps at batteries while "guestimating" what's needed, or something like that. And sometimes it's confusing for me about what the correct practices are. Still a lot to learn :)

[@jehugarcia]

I always stay below 1c for charging and discharging any battery pack. Think about it this way, you should not be charging or discharging a battery pack in less than one hour, Cooling systems are needed for achieving faster levels safely.

[@888marin888]

@@PablumMcDump And in that case, how do you know how many amps you can throw at those batterie modules. If one batterie has 2amp max charge current, is it the same when 200 of them are packed in parallel ? What is the max charge current of a 200 batteries pack. Still 2amp?

[@PablumMcDump]

@@888marin888 Imagine that you have 10 cells that are 18650s with 2500mAh capacity and a 1C recommended charge rate (from the data sheet). A 1C charge rate means that you put the full capacity of the cell into it in 1 hour -- in this case 2500mA, or 2.5A. If you have 10 of those cells in series, you would still only be able to chage at 2.5A, because your battery is still 2500mAh, but with a higher voltage. If you have 10 of them in parallel, assuming that your wiring/bus bars can handle it, you could charge at 25A, because you have a 25000mAh battery. If you did them in 2S5P, you'd have a 12500mAh battery, and could charge at 12.5A. See how it relates?

[@nazeryoshi]

Looks AWESOME!

[@charlesgomes9268]

Please share more info on your Daly BMS.

[@ayalaamaury]

You ordered paid samples or got them

[@AJAviator]

Any suggestions for a 8S Li-Ion 50A BMS?

[@richhagenchicago]

Is there not an issue with a reset from fault using the ssr vs just the BMS. I try to set my systems such that the BMS does not trip on the high or the low side. In my testing with just a BMS though, the system can reset if it gets to LVD and then gets a charging current which raises the voltage back up. If you have an SSR switch, it would not allow charging current under such circumstances and you would have to manually reset it. A recovery from high voltage cutoff would be similar in that simply turning off an SSR would also not allow the system to discharge, though the BMS might self discharge the over voltage cell as part of its balancing in that case, I have not tested that. That fault recovery would be a major difference I would think. What I would like to see is a BMS where I can adjust the min cell voltage where discharge stops, but charging is still allowed, and a maximum cell voltage where charging stops but discharge is allowed. I do not want to run my cells down to 2.5V or 2.3V before it stops discharging and cutoff voltages on the high side up to 4.25 or 4.28v as many of these BMS's seem to be set at. I would rather use less of my battery and get more cycles. I am using load controllers to set a discharge voltage for the various loads depending upon how important the load is, and a charge controller which at least limits the maximum overall voltage of the system to a 4V average. My hope is that My BMS systems on the paralleled battery packs that I have on my system are just a redundant safety that doesn't trigger a fault at all until near when the pack is failing.

[@jehugarcia]

Yes his might be an issue

[@woodtv4481]

I learned so much from this channel than reading books

[@fraziermit]

FYI, Sense is only single phase. You will not be able to see all phases on your 3-phase service at the shop.

[@lnxpro]

split phase. but yeah. if he's got 3 phases, he won't see one phase.

[@johnwatrous3058]

need something cheaper