Keep in mind I used a fairly steady load of 155 watts AC. If you test with a smaller load running for additional time, inverter overhead draw will decrease the usable watts. At the opposite spectrum a very large load will yield somewhat lesser yields as well. I chose my load amount simply because it is what my tv draws and is a decent wattage amount.
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I’ll try a similar steady load and see what I get. My results were mostly with a modern kitchen fridge and a couple DVRs which averaged around 170wh. The modern fridges don’t have the big current spikes like the older ones but its possible it might have affected the results somewhat even though a wh is a wh.
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Darn can’t use the D050S w/ the EB55 according to Bluetti
That is because the output voltage exceeds the input max voltage of the EB55 and the EB70
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Do you mind sharing how you added the step up converter? So far Google searches have been unfruitful. I assume I’m using incorrect search terms. Is there a video you could point me to?
You would connect a 12V to 24V DC 15 amp output step up converter (amazon) to your vehicle battery. You would have cables from the vehicle battery to the converter and then the converter output would connect your EB55 DC charging input cable. This will give you about 200 watts of charge and will consume a little over 20 amps of power from your vehicle alternator or battery. You can utilize a large manual switch or use a switched relay to power the unit anytime you turn your vehicle key on.
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I accidentally fell asleep w/ b230 charging a tablet and a charger (low demand devices) and when I woke up this morning the b230 was off. So sometime in the night it shut off. Both devices at 100% and the b230 still at 5 green dots. Not an official test just and observation and I think answered my own question.
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I had the same problem with the AC adapter port. I have a 15A adjustable DC power supply, set it to the correct voltage, but it doesn’t work. The bluetti appears to over-current the supply for a few tenth’s of seconds and then gives up the instant the supply voltage drops below 25V. This supply can do 350W+ so it definitely should not have been a problem. I think its a problem with the bluetti… it isn’t soft-starting its AC adapter and its firmware is giving up too quickly. I will try putting a big capacitor on my DC output (I don’t have it handy atm) to see if that is able to work-around bluetti’s surge current problem.
I am able to get the B55 to charge at 400W. 200W from the supplied adapter, and then another 200W or so from the MPTT by connecting that same DC supply to the MPTT instead of to the adapter input. Unfortunately, charging via the MPTT input causes the bluetti’s fan to turn on quite often (which is why I’d rather charge it with my own supply via the adapter input).
Another note on the MPPT… the drop-out voltage is 12.0V, which is way too high. That is why the MPPT input doesn’t work well with numerous car adapters. Either doesn’t work at all, or only charges at low watts. The drop-out voltage really needs to be lower, like 10.8V (and perhaps be a programmable option but most vehicles these days have regulated outputs so there’s no point having a lead-acid-battery-saver drop-out voltage on the MPPT). So you need to supply 14.6VDC+ on the MPPT input to get any decent current.
And since the max voltage is 28V, when I put my DC supply on the MPPT set to 27V, it happily charged at 200W via the MPPT (albeit with fan noise).
(I don’t frequent these boards but since Scott’s posting was the only one I found looking for a similar experience to mine, I decided to follow-up here for his benefit).
-Matt
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Thank you for the thoughts and advice
Matt, that seems to be the way to go. Scott and others have done this. I will try it on my EB150. I was going to try two batteries in series to get the voltage above the 16V minimum input. But, I decided to go with a 12V battery and a DC to DC inverter. I like that idea better because I can adjust the input current to a desired level. According to Scott, this is not necessary and it is OK to hook up batteries directly to the DC input cable and it will draw no more than 10A. However, it makes me feel better if I can limit the output current of the DC to DC converter (increased protection). Parts on on order. It might take a while because I overseas and things tend to move very slow here. BTW, I have seen a guy on Youtube that hooked up some electric bike batteries directly to an EB150 with no current limiting so I guess it is OK.
I got frustated enough that I (just now) wired up a scope on the power output of my DC supply and the bluetti (on its AC adapter DC input) basically took the voltage down to some set voltage no matter how much current that created. After around 4/10th of a second I think it then detected that the current was in excess of 200W and turned it off, giving up.
So basically the bluetti assumes that the brick will do the current limiting for it. That’s why it wasn’t working with the DC supply. The DC supply said “You want 15A? Sure, no problem…”, and the bluetti then at least had a safety in its software to say no. Its a pretty serious design flaw on bluetti’s part to not implement the 200W cap in the EB55 itself.
So with that figured out I put a lab power supply on it that I could set the current limit on. I set the current limit to 1A, 2A, 3A, 4A, 5A and the voltage to 27V. NOW the bluetti worked! It took the voltage down to 23.21V on my lab power supply with the current capped at the setting (1A, 2A, 3A, 4A, 5A)… and it happily charged at roughly 23W, 47W, 70W, 94W, and 117W.
Problem solved. I just need to get a current-limited switching power supply tuned to the charge rate I want that won’t make any noise :-).
-Matt
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I am surprised to hear that. From what I heard from others on this forum and also from some Youtube videos, as long as the voltage is within the specified input, the current will be limited by the input circuit (MPPT) of the Bluetti EBxx model.
The MPPT circuit does limit the current. However, the “Adapter” input that the AC brick plugs into does not. The Adapter input requires the brick to do the current limiting. That means that most DC power supplies won’t work with adapter input. Any supply which has short-circuit detection will trip off, and any supply that puts out more than 200W will cause the bluetti to give up and turn off the adapter input. (for the EB55 anyway). Only supplies with active current limiting (at less than 200W) will work.
-Matt
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Yes you are correct. I was thinking about the EB150 which has only one input. Maybe that is why it is OK to charge the EB150 without current limiting. I was told by Scott that the EB150 internally limits the current and that you could feed the DC input with batteries and no current limiting. I guess your testing was on the DC input and not the MPPT input. I wonder if you repeated your power supply test on the MPPT input if it would limit the current? Anyway, at least you resolved your issue.
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Hey. I just bought EB55 and i am suprised over powerconsume. I started USB and 230v outputs, with no load. After approx 8 houers 40% of power has been used. Anyone have any experience on this?
@tip67 Have you tried to calibrate the machine?
First discharge the machine to 0%, then charge it to 100% with the AC port. During this time it needs to be charged continuously, not disconnected, and not with a loaded device.
We suggest you try this first and then see if the EB55 still has this problem.
Thank you for your cooperation.
Yes, it uses power in proportion to the load you connect. More load, more power consumed and the shorter the battery life will be. The battery meter is a very rough estimate and will only be accurate within 20% as well
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