EASun SMG II Minimum PV voltage

[Alex1]

It's not a problem, thats how it's supposed to work. You should also aim for higher VOC with these inverters , 120V is like the minimum MPP working range. so its doing its best to extract maximum power from your system. Do you have any loads on the inverters output while you try to charge the lifepo4 ? are you sure the lifepo4 settings are correct so charching starts ? Do you have AC IN ? Have you set the correct priority settings ?

I think im high enough with VOC 8x longi 450 (49.3x8=394.4V), i dont have space on roof for more than 8 panels that big.
Picture from today. Drop between 10 and 11 was because of disconected wifi.
Yesterday i change output priority to SUB, because of 16Ah LIFEPO4 small battery was not enough for some real power, battery was full so today was no charging and no discharging.
I cant find how much generated PV power was per day (kWh)? is this calcucated somewere or not, because i cant find it?

 

[EliteSolar]

It seems its working fine. As far as i know , unfortunately there isn't total pv power generated

 

[CPet]

I finally got around to measure the power consumption. I mounted a wattmeter between the mains and the inverter, as can be seen on the picture, switched off the solar panels and let it run for 47 hours with nothing connected to the output of course.
Roughly ~900 watts were consumed, making it around 20 watts per hour. Not a lot, but considering we havent had any proper sun for more than a month, it is a bit silly.

 

[onobeka]

I think that is not bad at all. Victrons use about the same, and their units are quoted to be the low technical consumption ones. The inverter needs to maintain the connections hot in order to react to load switching. Do you have a battery as well? If so, can you also monitor the consumption from the battery next to the one from the grid when no load is connected or the output turned off? I guess it will consume similar from both sources.

 

[CPet]

Yeah it's not too bad, although it would have been nice if it entered a powersaving mode, when there is no sun for longer periods (like at night).
I don't have a battery yet.

 

[onobeka]

If you not have loads at night, you could turn it off from the AC in breaker.

 

[Alex1]

Mode SOL, Only pv charge is alowed setup, and I have some AC charging over night( looks like inverter is holding battery at 24V 21.12 from 19H, to 22.12 7H. Then voltage drops from 7H 23.8V to 8:40H 21V and JK bms turns dicharge.( I am using some old small lifepo4 battery cells 16Ah)
dont know what happened? disharge from 7H to 8:40 isnt on graph, there is just flat curve.
Is all this normal? does bms dicharge battery?

 

[Larry Oswald]

Yes, you would need at least 120v for the MPPT to consider the panels. But in reality you need to be around 250v or higher in order to get some real power under load, for you inverter model.

 

[Larry Oswald]

I use SMX II 3.6KW EAsun with five 360W panels. Agreed that the minimum to harvest power AT ALL is 120V so you will need a couple more panels. However with overcast more than my five panels' max 190V would probably help me as the loaded panels with weak light the voltage drops below that 120V minimum. Actully in that case the PV voltage goes to 140V or so, then the EAsun tries and the voltage drops below the 120 and the unit gives up. In summary: You might get more panels OR you might consider a different inverter with lower requirements. The EAsun emails are loaded with CHEAP alternatives, cheaper than buying more panels. My EAsun unit has been great although I never get close to the 3.6KW

Edit 10[13[23: I lucked into a sixth panel, twin to my five. The added panel has greatly increased the "balls" of my system. I guess this is due to the voltage /difference ABOVE THE 120V minimum. Compare nominal 240-120 to the 200-120 or 120 vs 80. Fifty percent increase? Not that much difference.

 

[masuka]

SAME



Not same , if I understand correctly your behaviour , mine is different . The grid will work like battery in my case , it will draw max PV always and add from grid whatever is needed. But my model is SMG II without an option to export and ct sensor , so its a different design.

Mine also flashes no battery connected but works fine.

For the record (since I'm referring the old posts ):
I have SMG-II 5.6kW running without battery and I have mixed experience that create some kind of equilibrium between both of you:
With very low loads my SMG draws 50% from PV and 50% from grid even in very sunny days, when it's plenty of power.
When load rises the ratio between PV and Grid power is changing to the favor of PV.
Ultimately...Grid draw stays about 190W even with high output loads (like 3kW or more)...
...BUT...if load jump from low to high suddenly (electric kettle, oven etc.) the rised load is first supplied from grid...then gradually it's moved to the PV lowering grid load to that ~190W
It seems that MPPT circuit needs some time to "realize" how much additional power is able to feed to the load.

Anyway...that behavior with low power load/sunny condition is little disappointing.
Next year I plan to buy batteries anyway.

PS:
Someone (in that thread) was trying to asses power consumption using clamp meter.
That is obviously wrong because calculation UxI gives you apparent power, not the active one.
In my case, with the load ~600 W clamp meter showed that my SMG draws from Grid 0.5A MORE that it gives to the load!!
But power meters wired before and after inverter showed otherwise.
So do not use clamp meters to asses the power...especially with low looads, when inverter is a capacitive load to the grid with really poor power factor (just as every high-power switching converter with low load I've measured )