EB70 - Solar input greater than 8 amps

I have read and am aware that the EB70 somehow maxes out the PV solar input at 8 amps. I have acquired the Bluetti SP120 (on its way) and recently as well a TopSolar 60 watt folding panel, their SolarFairy that folds down to a small bundle. Bluetti shows a 6.06 A operating amperage, and the TopSolar shows a current rating of 2 amps. In parallel, that approximates the 8 amp input on the EB70, I believe.

Just for my information, what exactly happens to the EB70 if the amperage is exceeded…is there damage, or does the MPPT just throw away the extra amps?

Is it just a matter of ~25 volts x 8 amps = 200 watts, or is there other math or factors to consider?

When you connect different type of panels in parallel, all the panels can only output the voltage of the lowest voltage rated panel. So…If your 120 watt panel operates at 20 volts and your 60 watt panel only operates at 15 volts, both panels will now operate at 15 volts degrading your 120 watt panel output. If the 60 watt panel operates at a higher voltage than the 120 watt, the 60 watt panel will now operate at the lower voltage of the 120 watt panel. If the voltages are fairly close, not big deal. If they are far apart you will not get the benefit of the additional panel that you would think. Basically add the amps of both panels and times that by the volts of the lowest rated panel and that will give you your potential wattage. X that answer by 80% and that will be more realistic in the real work under ideal conditions.

With regard to what happens if you over amp the EB70…The EB 70 will not allow any power over 8 amps and no damage should occur within a reasonable over amp situation. The Mppt does not not throw away any amps over the max of 8, it simply does not let in any amperage greater than 8. I personally would not be comfortable feeding it more than 200% of its max amp rating.

The only way to get close to the 200 watt max input is to have the voltage of the panels in the high 20s with 8 amps of current. Unfortunately, the practical max is going to be in the 150 to 165 watt range under perfect conditions.

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Does that mean that if I have 12 volt into the EB70, that it can only allow 12*8=96 watt into the units?

I’m like… I have 2 solar panels 18.5 Volts, and getting around 155 watts at maximum - one panel gives 83 Watts, so in theory I should have 166 watts yet connecting them in parallel only makes a maximum of 155 watts. Now I thought it was some kind of resistance, but if you only allow 8 Amps at all volts levels to pass - that’s 18.5*5 = 148 watts and I’m a little above that.
I thought if I added another panel, it would surely reach 200 watts - but that I should not expect?

This is rubbish… What a nonsense issue to run into. It says 200 watts on the intake, I expect it to do 200 watts in all levels of Voltage that the input is made for.
In any case I have ordered a bigger input cable for less resistance as I thought it might be the weakest point, I might get a little more out of it, but of cause if the unit itself does not allow more to pass then at least on the loss of power from source to storage does not seem to be the problem anymore. I did have a 17 watt loss that I fixed with 6mm2, although just a tryout to see what would happen 2*0,75mm2 into one wire 23 meters in total and surely a loss over 10% was seen, but it did work fine it seemed overall. But 6mm2 wires fixed the loss.

  • Darkijah - JesusGod-Pope666.Info

Yes, you are correct. You’d need to supply a higher voltage to achieve a higher rate of charge.

You might see slightly more power (maybe 10W?) coming in because the voltage drop from the panels as the station pulls amps will be less significant. In my opinion, it’s not worth getting another panel.

This is a frequent comment but is the norm across solar generators. You will not find any solgen that does this on the market. If a power station were to do this, they would need to adjust the DC input voltage. For the EB3A, EB55 and EB70 it would change from 12-28V to 25-28V because any power supplied in that 4 volt range at the maximum 8 amps results in the 200W charge rate. To accept 200W at 12V would require supporting 16.6 amps, twice the max amps in the current design, which would inevitably increase unit costs.

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Kinda would have been nice to know that I should have taught about the 25-28 volt thing for getting 200 watts into the system from the beginning. It’s not like they could not have written someone about it on the front. Like 200 watts at 25-28 volts. Beware 8 Amps Max on all Voltage levels.

I have ordered a 12 volt windmill… I think it will produce 12 volt DC and not 3 fase AC, but… not entirely sure how I will then add that into it all.

Thanks for the quick reply.

  • Darkijah

Are you planning to plug in your 12V windmill directly into your EB55 or does it come with a wind charge controller?

Its’ the EB70, and at the moment I have 2 solarpanels sunpower 110watts connected to it.
But I guess… connecting the 12 volts windmill even if it is 600 watts, won’t give more then 12V*8A=96Watts
I’m not entirely sure what to do, I had a look on a Hybrid controller for both Sunpanels and Wind but I think this windmill has its own controller and push out 12 volts DC already, and not 12 volts 3 fase AC…

So No entirely sure what to do.

  • Darkijah

Was looking at something like this, a Charge Controller for both Sun and Wind - but this Windmill that I have ordered seems to be already 12 DC with controller build in and power release and not 12 volts 3 face AC.
Here is the biggest version of the one I’m looking at, it exist in different versions of watts :

And this is the windmill I ordered: VEVOR 600W 12V Vertical Axis Lantern Wind Turbine Generator 5 Nylon Blades | VEVOR EU

Maybe I could get the Voltage up for the EB70 input if I had the hybrid controller and maybe there is a possibility to set it to 24 volt battery and thereby have around 25volts for the Bluetti input.

None of the Bluetti units officially support input directly from a Wind generator (not what you’re trying to do), less an external solar and/or wind charge controller. Before external controllers send power to whatever is connected to the battery terminals they typically first try to measure the battery voltage. If you connect a solar generator instead of a typical battery then it will measure 0.00V and think no battery is connected and thus not send any power out so there is the possibility your hybrid controller will not send any power to your EB70 because of this.

Could you put a 12 volt battery in between the 2, EB70 and the Windmill to make it charge maybe and trick it, I see I can charge my Bluetti with a 12 volts Motorcycle battery although slow, it seems good enough for my usage in the night needing power I can unplug the Solar and put in the 12 volt motorcycle battery to get a little more out of the unit.
But yea, I think the Windmill I have ordered has 12 DC out of the box with a controller and also watt security usage in it - and that would most likely not work with the MarsRock controller that seems to need a 3 fase AC Windmill.

Hmm I guess with the outside MarsRock controller, I could collect all the power, move it forward to a battery and from there on to the bluetti maybe… I hope the MarsRock controller can send 24 volts, it does seem to support it, but then I of cause need a 24 volt battery first. And then from the 24 volts battery to the bluetti, could this be done directly maybe without issues?

And yes I was thinking of trying at first, to connect the wind generator directly into the EB70 just to see if it works, but maybe I need a 12 volt battery between them to make that work? Just for testing and further improvement of the system as we go.

Thanks you guys.

– Darkijah

You could - that doesn’t seem like a bad idea, but best if someone else from the community could chime in if there would be any issues with this approach as this is getting outside my area of technical knowledge.

I don’t think you want to do that. First, checking the user manual, there are three cables that go from the generator to the controller suggesting it’s 3-phase AC - connecting this to your EB70 (which only accepts DC + and -) could damage it. Secondly, the manual also instructs owners to first connect a battery to the controller before connecting the generator - this is likely how the controller gets its power. Thirdly, " If a wind turbine generator is allowed to rotate in the wind with the batteries disconnected, it will start spinning at very high speeds because it is operating without any connected load to act as an electrical brake. This overspeed condition can cause mechanical damage to the turbine as it could potentially self destruct.". I recommend checking out Dump Load and Diversion Loads for Wind Energy Systems.

I understand the manual says 3 faces AC, but they seem to point to the manual that is mostly in regards of the other 2, the 600 watt version seem to be different from the 100 and 400 watt version, annoyingly enough. Because it does not make it easier when you then have chat responses and have them for all 3 of them if there is a difference. Well… I guess I will know when I get the windmill how it operates, but as far as I can gather it has a controller build in with over power protection as well if the battery is full it will dump it as far as I can gather in the windmill itself. And it seems you where tricked like I was to believe it was a 3 phase windmill :confused: So sadly I don’t think it even works with a standard 3 phase controller as I have looked at, but I guess it will do for a test to see if it even works in my environment, I have buildings all around me so it might not blow enough, but we will see.

I have been looking at some stuff here and there, a step up voltage, that could maybe be used for the sun panels and been looking at batteries as well. Was looking for some 24 volts batteries but… of cause I can just buy 2 12 volts and connect them, that seemed to be the cheapest way.

I wonder if one could connect 2 12 volts batteries in Serie and make them charge from the Windmill and make them charge in 24 volts to the bluetti? Or would I need to reconnect things every single time for that?

Just thinking up my options and all.

@JesusGod-Pope666 Check out this graph, might give you a better feel for optimal voltage and outputs…

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What is the last number at 30 Volts on the EB70?

I seem to have found a step up to 26 volts, although not sure if it works with the solar panels and even if it is worth it as you lose energy as well doing that step.
Then of cause the controller is a possibility as well, I have some ideas.
At the moment I am just waiting for my windmill to see what kind of connection is needed but scouting around for information and things and options.

193W should be the maximum Apparently from another, although the graph seems to say 197W.
I have been looking at step up like: https://pt.aliexpress.com/item/1005002053375089.html?spm=a2g0o.store_pc_groupList.8148356.12.465645e54y1w3I&pdp_npi=2%40dis!USD!US%20%2423.24!US%20%2423.24!!!!!%402101d91e16819239886542391e4726!12000018569822415!sh&gatewayAdapt=glo2bra
Or like:
https://pt.aliexpress.com/item/1005004296211545.html?spm=a2g0o.store_pc_groupList.8148356.10.16e9159fTByzCH&pdp_npi=2%40dis!USD!US%20%2428.74!US%20%2428.74!!!!!%402101f49c16819231884156192e7645!12000028667494655!sh&gatewayAdapt=glo2bra
Although you can lose up to 7% by conversion, but if you had more panels then me, like 3x110 watts panels it might be worth it if it works.

I don’t think you are going to find any combination that yields higher than 165 watts due to any panels voltage lowers the higher the load it is under. If you find a panel that will max out the 200 watt potential, the VOC starting voltage will be higher than allowed on the Bluetti.

Dear Scot I actually seem to have found a panel very very close to some great stats. Lets see if I can find the tap somewhere here. But I was somewhat worried of the Empty Volt stat, as it was 30v point something. I’m not entirely sure what to count from, some will count only from the Voltage under load so I was hoping the bluetti would do the same maybe, and be able to do it. Lets see if I can find the Website and panel.
Checking, Seems I on my mobile… So… But in any case…

Although if it is not, you can put as I understand a voltage step up between or a controller like the MarsRock that can potentially output 24 Volts if the panels are at a specific level of voltage input like in my place I would need to put the 2 sunpower 110 watts into serie and not parallel, and that output is set for charging a battery, and they support multiple, so that will be higher voltage then 24 and thereby should give you the possibility of reaching 200 watts whatever the case for the Bluetti charging station. These are 2 ways I can think out in theory!!! Then testing and then see if it works out :) That’s good science as learned. Although I do not know if you can put the MarsController directly to the EB70 Bluetti or need a batteri/batteries in between as a collector for power, I think you need batteries.

I think I have sorted something out in my mind at least… sorta, but it seems to change here and there because I figure out a problem.

by the way… I reach 160 Watts today on the bluetti display, although just for a small time, although I have seen 156, 157 and 158 watts on the display today!!! And for a very short time, 160 Watts was seen. So even with 18.8 usage Voltage it seems to be going up, oh I got the number 159w now just turning on the display. still 40 minutes before the sun is at its highest. How high it is possible, I don’t know… But it is still crawling upward it seems on my system even with the standard 18.8V from the panels!

Hmm my message disappeared and was apparently attacked from the political nonsense as spam. The internet has become so hostile these days.

You are going to find that around 165 is the maximum in and situation. If you select a panel that exceeds the VOC limits of the EB70, no charging will occur and damage to the unit is possible.

Okay just found this on a website:

Open-circuit voltage (Voc)

The open circuit voltage is the maximum voltage that the solar panel can produce with no load on it (i.e. measured with a multimeter across the open ends of the wires attached to the panel). If two or more panels are wired in series it will be Voc of panel 1 + Voc of panel 2, etc. The voltage is generally highest mid-morning as the sun rises rapidly and the panel temperature is still quite low.
The Voc + approx 3.5 per cent must be less than the maximum solar voltage permitted by the solar-charge controller. Some controllers shut down if it’s exceeded, while some may continue to operate but the lifespan of the controller could be compromised or it may result in immediate destruction of the device.

It seems to say the same as you do, but one thing is theory another is in practice, although trying it out would be expensive to do, and further if it ruined things or did not work wasted resources out the window.

I still believe you can reach near to 200 watts on the bluetti, if I can like put 3 110 watts in parallel then you should be able to just buy a step up voltage where you might lose up to 7% energy but get the voltage you want for the Bluetti! Or the MarsRock controller making it put out equal or more then 24 Volts for battery charging.

So… Just thinking what to do here… and my options. If you have panels that exceeds the wattage by a good amount, you could try to buy a step up voltage and see how it goes. I’ll give you a link so you get the idea.

https://pt.aliexpress.com/item/1005004296211545.html?spm=a2g0o.store_pc_groupList.8148356.10.16e9159fTByzCH&pdp_npi=2%40dis!USD!US%20%2428.74!US%20%2428.74!!!!!%402101f49c16819231884156192e7645!12000028667494655!sh&gatewayAdapt=glo2bra

And another, from another company, although seems the same.

https://pt.aliexpress.com/item/1005002053375089.html?spm=a2g0o.store_pc_groupList.8148356.12.465645e54y1w3I&pdp_npi=2%40dis!USD!US%20%2423.24!US%20%2423.24!!!!!%402101d91e16819239886542391e4726!12000018569822415!sh&gatewayAdapt=glo2bra

These makes the power into 28 Volts, which the Bluetti should be able to do. :)