Georg594

Start today on a cloudy / foggy day @Coulomb your theory about the input resistance of the voltage measurement is way off reality 😀 . Dont get me wrong but, if we calculate the input resitance 168v & 0,00065A = 260 KOhm this input resistor would create around 1 Watt of heat with a pv input of 500V, and that makes no sence. The firmware will calculate in 10mA steps right , but its so much tolerance in the measurement when current is below 0,1A that the inverter shows until 21W of PV input power (its way way of) (my axpert & EASUN made the same wrong measurements) ......real was at that time 0,14W. (Here will become another firmware bug activ >>>begins to load battery from grid with 2 amps if grid is available). advantage of this misbehavior >> Firmware starts mppt algorythm😆 The voltage of the PV input also changes in steps which would make sence that MPPT is already working. so i made another measurement on the inverter with isolation tester as supply for the pv input 2 . this time the current measuremt is in the wire between mppt pcb and main pcb . it looks like that the Algorithm searches and find the mppt point (positive value is current flow into DC Bus (still milliamps)) just look 😊 VID_20221210_133858_1.mp4

INTRO: Long ago i had the theory that Internal Supply of the inverter will cause currents on both mppts inputs which will interference with mppt regulation. NOW IT'S PROVEN: The simple solution is to pull of the plug on the supply pcb which is marked with "SOLAR". The downside: 1. Loosing of Batteryless Operation . 2. Inverter will not start from PV inputs when its switched off by the button to charge the battery. MPPT works now with a minimum current of 0.0002A really 0.2mA (first time i cant believe the measurement) FIRMWARE Modification is still needed but just only a littlebit .....not so much as in the past. @Coulomb Only the subtraction value needs to be zero, no longer need to set the minimum MPPT voltage higher than 90V or reset mppt code. Maybe we can even lower this for maximum compatibility.(eg 60v like in the twin models) Here a picture of the disconnected plug (on the upper right) The safest way is to completely disconnect your inverter from any powersource before pull of the plug . RESULT : I supply PV 2 input with a isolation tester which provide 250V MPPT point found by the firmware at 168V and 0,000487A WOW this is 0,082 watts 😅 MAYBE IT CAN USE THE MOONLIGHT FOR SOLAR PRODUCTION??? I'll check

@Coulomb checked your changes and everything looks perfect. @mjmx8k Do you have a dc clamp meter for measuring the real pv input current? (Beware of using normal series current measurements with multimeter because of the non isolated dc bus ) My axpert inverter has an offset of 0.12A until 0.16A on both mppts. If my inverter shows 0.2A the real measurements are 0.34A . Maybe this could be the answer 🙂😂

With Patched firmware 90.06 it looks like this (0.2A is the magic point)

If you read the complete thread you will find information about the internal supply which "stole" energy from both mppt inputs . If we disable this , you loose the batteryless operation.( Maybe we could steal energy from ac out from the inverter ). If the solar input is higher than 0.2A then it jumps over the limited 80-110v from internal supply. This is nothing whats happens in the firmware of the inverter.

Hi, My led bar was dead with dark red flimmer after 2 weeks of operation. Restart & completely power off did not bring it back to life. It seems to be an hardware fault . This happened without any firmware flash and was just one morning dark.

Test this 😀 minimum pv mppt voltage is 120V . this firmware 56.05 is nearly the same like my 8KW tweaked. so here comes your 5605 with the main tweaks of the 8 KW firmware i made. named it to 5606 . @Volker German brother 😀, this elemimated code sequence will do original a minimum shade managment. OG-10 DPS Reflash_5606.zip

The minimum changes to get it work as ist should is: 1 . The 90v limit rise to 120v. 2. The subtraction value down to zero.( @Coulomb you know what i mean ) The other tweaks are just for smoothing the regulation.

Hi did i see it right? 112.19 works in combination with 90.06 firmware ?

Today i got a new EASUN 8 KW it comes with firmware 46.08 main and 12.21 secondary. flash without any problems to 90.06 based firmware(90.09)

Made a 250V version on both mppt inputs, can someone confirm if eg. solar input is 1KW , the load is 2 KW on the inverter ( the missing 1 KW comes from battery) then the mppt regulation cant work if the voltage is higher as 380V . (i think the diode of the boost converter will become active because the inverter from the battery (48v to 360-380V) will provide maximal 380v (Limitet by firmware) , the boost converter can only make the voltage of the solar inputs higher than it was before . when now solar power is not enough for the load , internal BUS voltage drops to 380V and the mppt cant regulate in this condition , only between 380 and the low limit (original 90V) I change my configuration of solar moduls for testing and have now mppt point at 410V ........it drops to 380v if the solar power is lower than the load on the inverter . if please somebody can test this on his inverter and share results this seems to be an hardware limit because of the boost converter diode. 8KW.zip

Test for Internal supply 90v limit @Coulomb Grid voltage is 226v If I switch off the grid PV falls from 105 to 92 why ? If someone get informations please share .... Because if we disable the PV only option,PV could start at really nearly zero

Hi you are loosing power, not much, because your cloudy mppt voltage is near to 200V. An example : 200V and 0,5A = 100W 190V and 0,6A = 114W <<<< Best point 180V and 0,6A = 108W 170V and 0,6A = 102W The firmware is always searching for the best point, but here it wants to go a little bit under 200v but it cant . made a 175V version , everything else is the same can anybody confirm who uses any patched version the little 90 V step will become a 102v step when grid is available?? It seems the startup voltage from internal supply differs if grid is available or not . 8KW.zip

Hi, It seems you would need a 175v version. On the cloudy day with 200v mppt touches the limits.....here you loose a little bit of power . Please no donation 😅.....but I will make you a 175v version if you want it.

I got a really cloudy day with rain in the afternoon. Works like a charm

@Coulomb I think the original code to reduce mppt voltage when current is below a limit is to archive if one or two modules get shade to pull down the voltage until the bypass diodes will get active and so the other modules can bring full power..... But the code is so bad that there is no check if this routine makes it more worse ..... On professional Inverter it's shade management and really highly complex Maybe we can bring back this function but with intelligent logic

Maybe a look in the datasheet of PV moduls will bring us more information. Just have a look at the performance curve in correlation to sun power .....when you look there you will see voltage and MPPT point is always relative high If you think mppt logic is surging not enough current open your PV string and Check idle voltage....dont do it under higher power levels.... dangerous DC sparks will occur. Mppt calculates voltage X current= power ...and it plays with the voltage to archive maximum power . Look at my Trina tsm graph Maximum power is always at nearly the same voltage......

This is great to see how one step come to another. @Coulomb great work 😀

Ask yourself why flash tool doesn't get connected. Maybe the manufacturer is just stopping you to brick your device. By the way This is from my device

Don't attempt to flash a 90.xx version, until it's proof that there is a way .

Yours seem to be incompatible with Firmware 90.06 I didn't get the knowledge to tweak your Firmware Version maybe Coulomb will do it . The original MPPT works fine with direct sunlight.... only if not, then my tweak is relevant. My screenshot is a cloudy day definitely no direct sunlight.

Look at the solar power when it jumps....this is under 30 watts If you relate I got 4.4kw solar peak power it's just nearly perfect

If the voltage is below 280v MPPT will stop surging current.... But if you look at his configuration of 10 Canadian moduls in series.... there will be a current below 0.1A if you are at 280v.... then it will fall down to ~90v of the hardware limit.... At this point there is everything "pressed" out of it .... solar power is so weak that it's just useless Mine jumps in the morning from 89v to 380v when there is a current of more than 0.1A . In the evening the same but opposite.

Hi, changed both mppt min values to 280V named version to 90.09 8KW.zip

this is exactly what i want to know 😀 i will make you a 280V min (at pv1 and pv2) mppt version to get maximum performance. do you have 10 moduls in series on pv1 and 10 on pv2 ? did i got it right?