Inside a portable battery power station
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- Опубліковано 14 лис 2021
- Opening up my EcoFlow Delta Max to see what's inside and make a small change (which turned out to be pointless)
Affiliate links:
ecoflow.com?aff=138 (Works in USA only)
www.amazon.com/dp/B09D7N1ZV8?...
I’ll always respect the UA-camr who shows their mistakes and does not try and blame others in the process. This video just reinforces this channel as one of my favourites.
Yes he needs lots of blame....let's not let him off the hook.....
Matthias "Big Clive" Wandel
Second this! I wonder what Big Clive would have to say about this.
Maybe, Matthias "Canada Clive" Wandel, more apt and any Big "Manx" Clive fans would certainly recognize the reference.
The old ground loop through an instrument.... happend to the best of us...
Lol!
I killed a JTAG debugger that way. USB debugger connected to board under test and desktop PC, accidentally touched the ground spring contact on the oscilloscope probe to the wrong side of a decoupling capacitor. Enough current flowed that the tiny spring contact was glowing briefly. All I can say is I'm glad the only thing that died was the $100 debug probe and not the $4k oscilloscope or the desktop PC.
Yep. BTDT
Last thing I blew up was a lab made PSU, with some non standard features, lazy me did not isolate control board, and a DUT Made a condition where the loop was completed through that logic board.... Stupid as a fox!
By the way, and as Matthias mention Dave's eevblog; "how not to blow your oscilloscope" fits. The only thing that save this one was those old crt have a 1mm thick chasis, try that with a shiny new one... Lol!
Flips circuit board over...."I think I'm getting to the bottom of it"
hmmm....yep lol 😉
Cackle, didn't notice that, nice one.
I understand little of what Matthias is saying, but I still find it interesting.
The "epoxy" on that board is better known as conformal coat. One flavor of conformal coat can be dissolved with acetone, if you want to try the repair. Urethane CC is another variant and is much harder to repair.
A wire brush on a dremel would clean enough off around the pads to desolder it without nasty fumes.
Matthias and sponsored videos is not a great marriage, great video tough.
I think bessey could be a sponsor where the two would fit perfectly.
Why do you say that? I feel like he's the most honest and forthright about the actual sponsored content and exactly what does and doesn't work with the product.
Any revenue my preferred content creators can get is fine by me as long as the content remains the same and this unique situation they've actually provided since interesting content by being more free with the constraint on what he can and cannot show.
That look at the end when he mentioned the offer 😅
Pretty good sleuthing. One small correction: you need ~340V DC to generate 120V AC, not 160 as you said. If you say +/- 160V DC, that’s pretty close (slightly flat-topped, but it will run motors and rectify just fine).
i love the fixing electronics content. Do more of it please.
to be fair he broke it twice and didn't fix it
@@natalieisagirlnow yea I was hoping he actually repaired it but the fact that he didn't probably mean his assumptions were innacurate.
I have a tip for you. If you want to change the transistors, just cut of the leads und desolder them afterwars. That makes it a lot easier. And for the transistor. You need not to you the same. Goggle the data sheet of the original ones and search ones with same specs
I would desolder all of them and take them out still attached to the heatsink.
@@MattOGormanSmith that's a good idea.
I love watching bigclives teardown videos, it's super interesting to see something looked at from another perspective.
For what it's worth, some laptops actually do appear to be grounded between the USB ground and the charger neutral when plugged in. I discovered this while messing around with an Arduino Nano connected a Dell XPS laptop while examining output signal with a Tektronix 3052 digital oscilloscope. However, when the laptop is unplugged the USB ground then floats as you'd expect.
This is very likely just capacitive coupling. Switch mode power supplies (which all power supplies nowadays are) usually have an interference suppression capacitor between primary and secondary side, but are otherwise galvanically isolated.
Connecting primary neutral to secondary ground wouldn't be possible in a lot of countries anyway, because they don't use polarized plugs. Which wire is live and which is neutral depends on which way round you plugged the power cable into the outlet.
Most power supplies are designed for worldwide use and not one country, so they are built in a way that it doesn't matter which wire is live. (polarized plugs are a leftover from the beginnings of electrical wiring and haven't offered any benefit for decades as many countries in Europe, Asia and Africa will be able to tell)
It's like I once told my mother: you can't do anything to your computer that I can't fix. I, on the other hand, can break it much better.
They design these things against normal people doing something stupid. It takes an engineer doing something engineer-level stupid! But at least at the end, he'll know whether it was his fault. 😁
"I, on the other hand, can break it much better" gave me the laugh I needed, thank you!
So: 'The more you know about something, the more you can break it.' Now that is something I have never thought of...
Nice one :D
It actually seemed like a good review overall, you were very pleased with the circuitry
This is the video explanation of what I have *always* wanted to watch! Really good, love to see more of these if it's possible with you. I do like this portable power station...so let's see what you found. As it's very late here in the UK, I'll be back later in the week.
I've been using the Delta Max for about a week now. Encountered no problem whatsoever. It is pretty well built from the ground up. It's nice to see the circuitry in all it's glory.
"You must also watch EEVBlog videos" - why yes I do lol
Pretty good technical review of the Delta and really see what's inside this heck of a powerful power station.
So what you're saying is that after reverse engineering and tinkering you now have a couple of thousand dollars worth of boat anchor...that you can charge the trolling motor battery with. My electronics professor Ron Eli used to say, "Smoke test!". Great video Matthias, thumbs up.
The batteries, and integrated BMS (the board on the side he never shows) are likely just fine. That death-trap of an inverter should be thrown away.
That is why I always used an isolation transformer on my test equipment! but I can say I am from the days of Tube and transformers in my early days of electronics. hey I am still here and in Texas too! thanks for the video! I found you several years ago due to wood working like so many others. I like your approach to things.
Good Video! , its good to see a more humble side of the wizard!!
Great to see what's inside these power generators. They are very well built.
I think you would like the Fluke 43B power analyzer. It's a pretty old device so they can be found relatively cheaply on EBay. It measures and records pretty much everything you would care about in videos like these. Plus, it's a decent-ish scope meter which is fully battery operated and rated for these high voltages.
I had to buy a new battery for mine since it was toast, but I have been absolutely loving the ability to watch and record transients...
Thanks for posting an honest video. I’m sure Marco Reps would have added a laser to a repair of that.
I love watching your videos even when I have no idea what you’re talking about
That inverter circuit is so interesting. Thank you for breaking it (down) :)
I'm impressed by your electronic knowledge. Respect!
Next time, you can use a differential probe for best results.
That's why we love you, Matthias!
There is an elegant topology for power electronics where the inherent large area PN junction in a power MOSFET is used as part of a rectifier in a H-bridge configuration. This looks like to be similar to that
great video. love this stuff. kudos to the manufacturer for letting you publish. actually makes me more willing to purchase.
its called freedom of speach
@@Total_Egal The first amendment does not apply to private organizations, and certainly doesn't apply to anything in Canada (they have freedom of expression, which isn't quite the same thing). Had Matthias published this video without permission, he might have opened himself up to legal action.
@@F3Ibane i am not a USA Citizen.. almost the whole world ist not USA.. the Idea of fredeem of speach is what i was refering to.
the point you start to argue about whats private contract, whats a nda, do you need permission to say something and whats the exakt meaning in the words in the first amendement, is there a legal action.. all that is the problem..
the solution is get your and everyones freedom of speach back
dont sign such contracts and dont make such contracts and dont let them take legal actions against others.
@@Total_Egal *Speech. For something you're so concerned about, you'd think you'd be able to spell it.
@@bittrippn6570 Or maybe he's secretly a strawman planted by the corporations to make us think that smart ideas are actually dumb.
Well that's a bummer that it's busted, but thanks for showing the innards! That is fascinating that it's using the same circuitry to charge and invert. I sometimes but don't often watch eevblog, too long winded and too many irrelevant opinions 😉 I do watch a lot of big Clive!
totally agree on eevblog
I rather like Dave :(
the input circuit is a DAB (dual active bridge), quite a popular topology for smart grids applications
I love these deep dives, like you're solving a puzzle, it's great to see :D
Can the batteries in that really self discharge below safe limits? That seems like a huge oversight on their part o.O
Yes, this is true for ALL lithium battery chemistry. External circuitry can only make it worse by taking electricity out of the battery.
Ahhh, so this is why my ryobi batteries won't recharge.
I got a few back to life by applying straight dc from a working battery to give it "drink" then put it on the charger. I know the charger needs to see some voltage before it starts charging.
Didn't work for all of them.
@@richardpatterson4312 That is the same thing you can put a battery on the charger and it can show the normal voltage but soon after disconnecting the float drops back down
@@richardpatterson4312 If you have a good benchtop PSU, you can try to recover them. (But always assume the batteries are unsafe after, and keep them in a fireproof area when charging and storage). I've generally found that if the cell has more than 2 volts then it is fine to very slowly charge it up using a constant current source. Anything lower and you have to start worrying about dendrite formation.
@@richardpatterson4312 The "charger" is inside the battery itself. All the box does is provide a fixed DC voltage to the BMS circuitry inside the pack. If the logic has seen the pack go too low, it will not allow recovery. If you open it and attach an actual (CC/CV) charger to the cells directly, it might be salvageable, but any deep discharge damages the cell(s).
My guess for the reason you see the voltage spikes superimposed on the waveform is that the DC bus capacitors are specced for nominal load, whatever that would be. During startup, when a high current is drawn, the ripple generated by the full bridge boost converter appears on the output.
Based on what i've seen so far I'm pretty sure a few more hours of contemplation will allow you to identify suitable replacements for those transistors.
Yeah, I'm sure a suitable replacement shouldn't be too hard to find. It only needs to have similar specs (or better). Even if the specs are way different, he could overcome that by replacing all four, so they still match, as long as the new ones will work for the intended purpose.
For occasional emergency use, I like the idea of the power packs made by Ryobi, EGO and others that let you use your existing yard tool batteries. The downside is that they can be very expensive even without the batteries and extra batteries can be very expensive.
thx. i watched the whole thing.... understood basically zero, but one day I may learn.... keep up the videos!
Time for a collab with ElectroBoom :D
That’s one heck of a pile of electronics. He’s right about how all of the power charging, converting and generating systems are integrated in one box including the batteries and connections. Managing all that with discrete components could be a pain.
I used the same calculator 10 years ago in college. It's the best!
to look for short circuits in electronics I use a variable power supply AC or DC mostly DC, then I slowly turn up to about 100-500mA then you look with a thermal camera or feel forward with the hand, it works 90%. Another thing, never ground on an oscilloscope. You could use a transformer on the output of the ecoflow to go from 120v down to 15v AC with a 1Kohm resistor between the wires and measure there. I think it is the saw that makes these high frequencies but test it with an oil radiator or electric patio heater.
massive respect ecoflow
Talking about circiut boards like that....is like magic to me o.O
I understand very little of this but love watching it.
They make cheap differential probes for scopes now. I alway use them for mains power stuff now having also thought I was too smart to ground short something…
You don't need exactly the same FET, check the maximum voltage and current rating and choose one with equal or smaller rdson (on resistance of the drain-source) and gate charge. It's a good idea to change the fet driver too if the gate is shorted.
I can't even find specs for the ones on the board.
@@matthiasrandomstuff2221 Want to share the part number? I work in electronics, might be able to find something here.
Wow! I'm the TX guy looking for a frozen winter power source. Thanks for the video.
for that, a generator would be better, like I said. Unless the power fails very often.
I would lose sleep. There is no way I would not get that thing up and running again. The transistors have to be available somewhere or at least cross-reference some that are compatible. Thanks for the vid!
Of course, I was still there (11:00/01). 😅
I enjoy your channels!
OMG the look on your face at the outtro made me laugh so hard.
Matthias, thanks for the video.
Thanks for the info, guess it's time to get myself a Delta.
An interesting thing I've learned is that most of these inverters, whether modified square or pure sine or grid tie, none of them use boost converters. Instead, they take the DC, convert it into a high frequency AC (10s of kHz, still battery voltage) with the first H bridge, then use a small step up transformer followed by a rectifier and capacitor to convert back to DC, and now it's the 170V or so we need for the second H bridge. Just like a standard switched mode power supply, except it steps up instead of down. Now that feeds into the second H bridge.
So I wondered, why the hell have 2 H-bridges instead of just using one at battery voltage & the line frequency (60Hz) and stepping that up? Well, it turns out, if you want an equivalent transformer with the only difference being lower frequency, it has to be much bigger. I'm still not entirely clear on the details but it has something to do with the inductance/permeability of the core. Also, I believe for a pure sine inverter, the filter inductors would need to be absolutely massive, too, because they'd need to be pushing hundreds of amps.
For anyone who wants to delve deeper into this, there's a guy named James Fotherby who has been building an inverter very similar to this one. He's got some incredibly good information, super valuable resource jamesfotherby.com/index-page/
EDIT: I also wanted to add, I have an old modified sine inverter that I've taken apart. One very interesting design feature is that the second (HV AC) H-Bridge is completely isolated from the rest of the circuit. It's got an opto-isolator going to the MCU, and aside from that its only connections to the outside world are the transformer (input) and the hot and neutral wires (output). The ground comes from the battery side of the board and is tied directly to battery negative. The only components that are in the isolated side of the board are the part that filters the output of the transformer, and the H-Bridge itself. Pretty elegant design really. I'm not sure why they didn't do that in this one, because it makes the neutral truly floating.
I was thinking 'just like the eevblog video' then you said it. Haunting.
Tough luck, but you are not the first victim of ground return damage. After all this effort, maybe Ecoflow could consider repairing the unit - that would be great PR for their company.
If he had only opened it up to inspect it sure, but once he took a sawblade to a pcb that's just lolno. The warranty is far beyond null and void at that point. We all know he knows what he's doing but such destructive modifications shouldn't be rewarded with a free repair
@@Koushakur They should at least give him a link to the transistors
My delta 2 is out of warranty, won’t charge anymore is there a way to change the battery cells? Or do I have a paper weight? Lol thanks for your time
@@johnpaul9830 I'm not sure I can help much - either the charging circuit is faulty, or the batteries are dead. You need to disassemble it, isolate the batteries from the unit and use an external charger to check if they can receive a charge. If they don't, you need to source similar battery cells and reassemble a pack. Then, connect it to the unit and check if it charges. Not an easy task, that requires some skills and experience on these matters.
good infos and and NOT hidden mistakes
Nice the disclaimer at the beginning... I would verify if those are MOS or IGBTs, then find some that comply more or less with voltage and current requirements, and give it shot...
The closest to it I could find I think was a darlignton transistor.
I have seen UA-camrs promoting this thing -- I feel like I have an application for this in that I have some land that is over a mile from the power lines. TBH, the cost coupled with what seems to be it being sensitive to abuse (those computer fans) makes me feel like a little gas generator is better. BUT, this would be tempting if the price per watt hour was half.
At $1000 to $2000 for each of those power stations I'd seriously set about repairing the broken one. Transistors can be replaced easily enough. A Hakko FR301 desoldering pump will make short work of removing the solder from all the transistor pins. Use a Dremel wire-wheel to remove the conformal coating first, then pull the heatsink out as a unit. To search for the transistor try some of the electronics forums. The device is still in production so I have to assume the transistors are too. You just have to find out the correct designation as that's not always obvious by looking at the cases. If they really are not available then the forums can help you find equivalents.
This video is a not-so-subtle reminder of how I nearly failed basic electrical in electrician A-school
What transistor model is it? I've had some good luck with finding replacements (or suitable substitutes).
I've definitely done this at least twice... You'd think you'd learn after the first time
I haven't watched the part where you tell us how you blew up the inverter yet, but I reckon you just blew the IGBTs. That's easy to check, and if indeed the case, probably easy to fix ☺️
John Ward did a good explanation about using oscilloscopes with isolation transformers to avoid this.
How many do you think you will sell?
That's still a terrible idea. Just buy a differential probe, and you will never have to worry about earth ground problems. There's plenty of affordable probes on Amazon.
If you hook up the oscilloscope to an isolation transformer and not the device-under-test, I really hope you know what you're doing. Don't suggest that to anyone who can't at the same time tell you why it's generally a bad idea.
@@superdau hook the item under test to the isolation transformer
EEVblog-Matthais collab of the decade.
Really well done all things considered. I think you're selling yourself short though about fixing it. I'm sure some nerds can find a compatible MOSFET/IGBT whatever that thing uses and it wouldn't be too bad to swap them out with a proper desoldering station. Desolder all of them and remove the heatsink and transistors in one shot so you're not trying to access those screws behind all the components.
Yeah, there's probably a sizable range of "close enough" compatible MOSFETS he could use. Even if he can't get two more with specs comparable to the two that still function, he could just go ahead and replace all four to keep them matching.
@@SuperDavidEF Agreed. Though finding parts like that can definitely be a needle in a haystack sometimes.
So the AC output is from full H-Bridge, does it mean you cannot have one pole of the AC bonded to the safety ground/circuit ground?
Nice. I remember you saying once you were an engineer (?) at RIMM. Did you do hardware?
Taking the covers off a device and poking around inside is one way to learn about it. Of course it may destroy the device. This exercise may have accomplished your goal to reveal how this device functions and that has value. It would also be helpful to know what information the manufacturer would share with you or any other buyer of this product. Now you have a chance to find out what their technical service can offer to repair this power station. I imagine it’s well worth saving it.
Interesting.
I kind of like your University degree's line of courses that I had read or heard was a bit of a mix of engineering. It seems to have given enough electrical engineering in addition to other areas to be pretty useful. I on the other hand on puzzles like this have to start from scratch because math theory is about as removed from practical application as possible to achieve.
I'm curious to know how it works backwards from AC source to charging the DC lithium batteries
Very interested and helpful. Thnk You from Ukraine.
Very good video 👏
Great video.
Sounds like it could still be charged at a slow rate off solar panels, so still somewhat useful and better than nothing.
“By seeking and blundering we learn.” ― Johann Wolfgang von Goethe
To be honest the video is not pointless, because you did the tedious process of probing the board and give people a general understanding of the layout. So if there is at some point a person with a broken one and they are determined enough to repair it they have some sort of reference. And no, I don't watch eeev blog videos ;).
I watched the whole video but I guess I missed it.....did it fail on its own or was it user induced? If user induced was it because of tinkering inside the unit with the hacksaw blade? Surely plugging the unit into a power strip or having a Kill a Watt plugged into it when powering a circular wasn't the caused for it to take a dump was it?
This is probably also a good video for lawyers. Why you need to include those lengthy legal disclaimers for your products.
yeah
You should use an isolating transformer!
Ultrasonic bath should get rid of the coating if you ever fancy fixing it.
Great video
Also, your link goes to a 404 page.
I guess you'll never hear from them again!
I think an isolation transformer for the scope would've saved you there.
Good discussion! Yeah, the ac charger circuit is pretty sweet. Reverse inverter battery charging is so cool. Very unfortunate that you fried it! haha I hope you post a video when you get it running again.
Hah, I don't know why I was surprised to find you here XD
actually if you want one of these for emergencys, just cycle the battery every week or two to keep it fresh.
So if you had not ruined the boards….
Would it be possible to swap out the battery either a 48v LFP drop on replacement or server rack battery?
I know it won’t fit in the box but would be great to still be able to use the unit itself
I always applaud people who fix their own stuff. However, Ecoflow has an excellent warranty. I had a Delta Pro that can take up to 150V solar input and a Delta 2 that only takes around 60V. Well I was messing around with the solar inputs one day and mixed them up like a moron. The Delta 2 wouldn't turn on and had the lovely burning phenolic smell. I checked the fuses and they were OK. After messing with it, I contacted Eco-Flow. They sent me a replacement free of charge even after I told them it was my mistake. (I did help them troubleshoot some SW bugs on their other models so maybe they took that into consideration. Who knows? Worth a try to warranty even if you screwed it up.
YOU are very clever!
So is it a secret what's written on those power transistors?
Another funky resourceful thing done by some electric cars is to use the motor as an inductor in a switching charging-from-the-mains circuit.
Ok, this is the same failure I experienced on my EcoFlow DeltaMax2000 when trying to charge directly from my travel trailer breaker panel. So… exactly what would be the best work-a-round to prevent this failure? Not connecting the charging cable ground wire to the RV breaker panel neutral bar?
We need a Matthias and electoboom collaboration video discussing this topic. Tons of confusion between neutral and ground to the uninitiated.
haha. I have no idea what you're talking about but i still enjoyed the video.
Your 'scope probe is connected to ground? Strange, usually the probe connection is floating, and there is a ground terminal on the scope for if you need to ground it.
Not strange at all, probes are almost always grounded. That's why you never measure differential voltages without a differential probe.
@@sycc66 Strange- I have been using 'scopes for over 50 years- have even built them. Never met one with a grounded 0v line. Have seen front panel links so you can ground them, if desired. Isolated is essential for audio work - otherwise you have a ground loop.
@@Tensquaremetreworkshop I am guessing it has maybe been over 50 years since you bought a new scope then? As far as I can remember, all the scopes I have used were grounded. They have a pictorial indication on the panel that the outer shell of the BNC connector is grounded. Mostly compact tektronix models. I have been doing this for 20 years, so you have seniority on me.
@@mckenziekeith7434 You are correct that my 'scopes are of some vintage now. It may well be that recent models are grounded- my question would be - why? What advantage would permanent grounding convey? Optional, yes (front panel control) but always? Clearly, as this video shows, it has downsides, so why do it? Cheaper can be the only reason that I can see, and that translates to inferior. I guess they are usually used for logic circuits these days, but that is a poor excuse.
Isolation transformer... Is what we should all learn from this video.
Sad that you can't source the transistors. With a unit that is nearly useless, I would certainly attempt a board repair to revive. Right to Repair hindered again by supply chain issues.
There's probably a real close alternative though. Look for the same package, the same pinout, the same voltage rating, and for Rds_on and input capacitances that are in the same order of magnitude. That'll probably work just fine.
Nice friendly jab at EEVBlog. I can't really make it through one of those...
He's got interesting stuff, I just wish there weren't so many words between the interesting parts.
I am an electrical engineer. Every time I start watching his videos I look at how long they are and despair. He is smart and I like him. But his videos are too long for me. Also, since I am an EE, some of the stuff he talks about I already know. That makes it hard to hang around for the bits that are new to me.
Why does everyone in videos disconnect the positive battery terminal first? it's much safer to disconnect the negative first if it's negative ground because that will make it so there's less places (metal chassis or ground planes) to short the terminals across.
You had 2 can you connect the damage units battery in parallel? And have greater overall capacity?
The other one is just a battery extender, no inverter in that one.
Very interesting, but where are the electric shocks and explosions?