Hi

Have not had the time to work on this.

Hope to in the coming holidays.

need extra hands to help.

still hasnt changed. during the day if using appliances etc we get max +-1500w on a clear sunny day.

after loadshedding when batteries are charging up.

The inverter will run around the 1300=1400w on pv input but on battery charging indicator it shows around 700-800w.

 

 

 

 

On 2021/10/10 at 12:30 PM, Twakdaddy said:

Good day to all,

I'm finding that my system is only giving roughly 50% of the capacity of my solar arrays rating in full sunlight?  I'm puzzled as have tried everything!

 

I have the following components:

3 x Axpert King 5KW inverters in parallel (FW U1 71 97)

12 x 315W Jinko Cheetah panels 3S4P on 2 of the inverters (total 3.780KW each)
10 x 415W Canadians 2S5P on the other one. (total 4.150KW)

2 x 3.5KW Pylontech Batteries.

I find that i rarely get more than 2.2 KW per array?  I have checked each string and all is connected correctly.  I'm wondering if there is a setting that might be limiting the solar output of the inverter?

 

Any advice would be greatly appreciated.

I have the same issue.

 

Off-grid setup.

1x Kodak 5.48 OG plus (Axpert King clone) FW 72.00

4x Trina Solar 330W 2S2P = 1320W

My old RCT 5kw inverter gives ~1200W, MPPT ~64V ~18.75A

New Kodak OG plus ~600W, MPPT ~63V ~10A

 

Changing the solar string to 3S:

My old RCT 5kw inverter gives ~830W, MPPT ~96V ~9A

New Kodak OG plus ~400W, MPPT ~96V ~4.5A

 

The conclusion is inescapable, the new inverter only delivers 50%.

 

I have contacted the distributors Blue Mountain Energy, have yet to be advised further.

I have noticed an interesting behavior since connecting to the pyelontech BMS instead of just using the USE settings for the battery. The solar output of the inverters is directly tied to the charging rate of the batteries as provided by the BMS. I.e if the batteries are bellow 89% and accepting a higher charging current the inverters will use 5000w solar. if the batteries are 90% and above and request a lower charging rate the solar power utilized is only 2000w. 

it seems that old confusing setting of limit PV power to max charge current is enabled, but there is no option to disable this. I am not sure why this is but I think it could be the answer to the limited solar utilization people are seeing.  

 

Perhaps @Coulomb could advise if this is something in the firmware or a safety thing to prevent overcurrent events to the battery?

 

This is not my issue.

I have 3 batteries requesting 90A charge.

Inverter is setup with Batt BMS. It is asking for 90 but only getting 42A currently.

12 x 335W J Solar panels.

1 hour ago, Luan said:

The conclusion is inescapable, the new inverter only delivers 50%.

Seems like the OG 5.48 has a high voltage MPPT, so 2S panels will have too low voltage for the MPPT:

I'm surprised it even does anything. If that is the case, you will have to put more panels in series.

6 minutes ago, P1000 said:

Seems like the OG 5.48 has a high voltage MPPT, so 2S panels will have too low voltage for the MPPT:

I'm surprised it even does anything. If that is the case, you will have to put more panels in series.

I have the Kodak OG 5.48+ (The plus model has a MPPT of 60~115VDC)

1 hour ago, Luan said:

I have the Kodak OG 5.48+ (The plus model has a MPPT of 60~115VDC)

Yes the plus has a low voltage MPPT and 2 panels will be fine. 

Wonder why the power is so low. 

Edited May 12, 20233 yr by Scorp007

I had simmilar issues with a licensed Axpert ... try to put some load on the load side, just for tests, and see if the PV increases.

5 minutes ago, Jaxone said:

I had simmilar issues with a licensed Axpert ... try to put some load on the load side, just for tests, and see if the PV increases.

The issue is independent of load. Starting the borehole(0.75kw but pulling 1.1kw) or booster-pump(0.25kw pulling 0.38kw) simply pulls the excess watts from the battery.

10 minutes ago, Scorp007 said:

Yes the plus vas a low voltage MPPT and 2 panels will be fine. 

Wonder why the power is so low. 

I even tried 3S, for a dead middle of the MPPT range 90VDC, only 50%. Connect the RCT 5KW and I get 100%, plug in the Kodak 50%... gotta be a hardware/software issue with at least a few units, I am not the only one.

I am using a Narada battery, on USE settings, I use the RS485 on the battery for my ICC connection, I am not even sure the Narada could talk to the inverter nor do I really see a need to.

For me the problem was solved by adding more panels and increasing the voltage of the strings. I had to go from 9 panels per string up to 13 (380w panels) to see it working properly.

what is more interesting is my king inverters on 71.97 do not display this limiting behavior but the ones on 72.00 do. What firmware versions is everybody using?

I am on 71.97

39 minutes ago, Jaxone said:

For me the problem was solved by adding more panels and increasing the voltage of the strings. I had to go from 9 panels per string up to 13 (380w panels) to see it working properly.

This specific Kodak cannot take more than 3 in series depending on the panel voltage even 3 on a normal temp day can blow the Voc=145V MPPT. 

I still find it strange that Kodak use the Plus tag for the lower spec while on Axperts it's a higher spec MPPT. 

Edited May 12, 20233 yr by Scorp007

8 minutes ago, Scorp007 said:

This specific Kodak cannot take more than 3 in series depending on the panel voltage even 3 on a normal temp day can blow the Voc=145V MPPT. 

I still find it strange that Kodak use the Plus tag for the lower spec while on Axperts it's a higher spec MPPT. 

The plus spec allows for parallel operation, thought id pay the extra R1200 for the possible upgrade path.

Will be having the RCT inverter serviced and will probably just put that back. I got the Kodak installed 12 days after purchase, and noticed the issues 13 days after, had I gotten it all done within 7 days I could have just returned the Kodak inverter for credit and take another model.

 

8 hours ago, Luan said:

1x Kodak 5.48 OG plus (Axpert King clone) FW 72.00

The Kodak is not a clone; it's a legitimate Voltronics made inverter. Unless of course a clone maker is using the Kodak name, and you have one such. I've not heard evidence of this.

 

14 hours ago, Coulomb said:

The Kodak is not a clone; it's a legitimate Voltronics made inverter. Unless of course a clone maker is using the Kodak name, and you have one such. I've not heard evidence of this.

Sorry yes you are correct. It is not a clone.

I still have the same problem going almost if not over a year now.

Gave up trying to speak to guys at supplier Voltex.

Still waiting for a tech guy to return calls.

 

8 x 480w panels is 2s4p setup and have not had any luck trying various this suggested.

2 panels i tested at a neighbours place and he gets almost double the generation from the panels.

this was checked on a clear mid morning within a 1.5hours.

On a good day, max i have seen generated is 1.7kw. general usage it will be between 1.1-1.4kw. with the microwave on with

total draw just over 2kw. add kettle draw goes up over 3kw and generation is no different.

Currently serves it purpose for charging the batteries for load shedding and during the day covers the general consumption in the house around 700-800w.

Been saving up to do a upgrade the inverter and to add some more panels.

On 2023/05/12 at 7:07 PM, Luan said:

Connect the RCT 5KW and I get 100%, plug in the Kodak 50%... gotta be a hardware/software issue...

A thought in passing. The Kings (originals, not the King IIs) have the same 145V max solar charge controller as the Axpert MKS models (not including the MKS II models). These are an interleaved design. Essentially, there are two buck converters that are connected in a clever way to produce smoother output. The key point is that there are basically two converters there; if one was to fail and produce zero output, the combination could still work but produce exactly 50% of normal power.

Since your output seems to be quite close to half what you expect, it's possible that one of the two buck converters is not working. It might even have been like that from the factory, and maybe they didn't notice because it still provides output. Pretty poor testing if that is the case.

So if you're handy with electronics, you might be able to repair it yourself, using traced schematics and other resources. If you're not, it might be worth trying a new MPPT module rather than replacing the whole inverter. If I'm right, it does at least point to a hardware problem rather than a firmware or configuration issue.

Hi Guys,

 

my 2 cents,

These are my PV values from my 3 inverters on a winters afternoon.  I have physically measured the current and voltage from each array and it is same as the MPPT values displayed above.  When I manually calculate the power I get 2,7417KW,   2,8272KW and 2,625KW.  As you can see the inverter displays are about 3KW down in total on my manual calculation?

 

So the question is, is the summing function incorrect and the inverters are actually delivering the full power but it is only displaying incorrectly or are the inverters throttling and throwing power away?

 

I will measure total power output from the system manually when I get some time.

 

The powers and currents are consistent with the "MPPT current" being the current at the battery (not PV) end of the solar charger. It's a buck converter, meaning that the voltage is reduced (bucked) but the current is increased (boosted) through the converter.  Voltronic are never clear about which current they are reporting, so it's not surprising that the monitoring software is a bit misleading too.

Note how the PV power divided by the "MPPT amps" gives a number between 49 and about 52. That's your battery voltage. So just read the "MPPT amps" as "MPPT output amps".

I don't know why you measured the same current (I assume this is PV current) as what the display say. Perhaps the current jumps around a lot so you can't get a valid comparison. Or maybe your solar charge controllers are all reading way too high.

Hi Guys,

Just a quick update from my side. I have had zero joy with the distributors of Kodak, Blue Mountain Energy, no info, help or feedback, they only answer phones when they feel like it and have zero customer service. Will be returning the inverter to where I bought it, Communica, they say it must be sent back for testing... blah blah blah.

 @BritishRacingGreen helped getting my old RCT going again, he is an absolute legend. See attached the difference after I swopped them back.

 

Hi Guys, I assume that no one has managed to crack this?  Apart from putting in different inverters?

Please see attached image. It seems like the kings are trying to put out full pv but then throttle back?

Penny for your thoughts?

 

I have a kodak 5.48 plus and solar assistant to monitor and have noticed a similar situation. Tho my pv input reads low but is able to power a 1500w load and charge my battery at 1700w...

Noted my inverter seems to read the amps and volts correctly but doesn't covert correctly to watts and solar assist just take the watts and volts readings and converts back to get the amps.