Deye sun-8k-sg01lp1-eu clips production at 20A in one of the MPPT

[Propalen]

Hi all

I have a clipping issue on my installation. My installation consist of

- Inverter: Deye sun-8k-sg01lp1-eu
- Solar Panels: 18 JA Solar 550W.
- Wiring: Two MPPT in use. First one with 8 panels in series. Second one with two string of 5 serial panels (5+5)

I have a problem in the production that can be easily spotted on the main production charts (see below). My conclusion is that the MPPT 2 (5+5 panels) is clipping at 20A. However the device specifications on the User Manual and Inverter sticker indicate a maximum of 26A. Please let me share some images to back my findings:


Day One Sample (31/05). Current peaks at 24A at 12:23 then it is clip at 20A for the rest of the day till the evening. There are no shadows afecting at that time.

Day Two Sample (03/06). Current peaks at 25.10A at 13:04 then it is clip at 20A for the rest of the day till the evening. There are no shadows afecting at that time.

The device specifies a max PV Input current of 26A both on the side sticker and user manual.



Where the issue might be?

1. I have seen other discussions that the PV Input may be limited to 20A by the manufacturer. Please see link below.

https://powerforum.co.za/topic/11215-deye-8kw-mppt-current-clipping/

Is that correct?

2. I have been scammed and my inverter is an older version with a fake sticker that only supports 20A max PV current.

3. I required a firmware upgrade. Is my current version the latest (see below)? How to upgrade the device?

Current version 0-6024-1724

4. I have missconfigured the device. See system work configuration below



Please share your thought and thanks for your help!

 

[shadowmaker]

Doesn't look like clipping as then it couldn't go past 20A at all and production "curve" should be a straight line exactly at 20A. At least my deye12Ks do it that way at 26A. That said, I don't know what is causing your production loss. Looks like thin shadow from maybe power line, antenna, etc or panels heating up over hot roof, but just a guess.

 

[Propalen]

I think these are bad guesses. If it would be a shadow or a heating issue, it would show always at almost the same time for two sample graphs separated 3 days. The overheating option should follow the same argument.

The most likely is clipping triggered by a hysteresis filter. This is, the device will not clip till an overcurrent is reaach (24/25A) and then lower the current to safe value (20A) for a certain amount of time.

However I am interested to listen to other opinions. Anyway thanks for your contribution

 

[kommando]

If it was clipping why does it go over 20A in the morning and later in the day. Shadowing would be closer in time but heating of the panels depends a lot on wind direction and speed plus the sun intensity so power reduction times will vary.

 

[Norwasian]

I'm no expert on this, but have a slim-chance thought: it might be the software settings in the device. I don't have a Deye, but bought the LVTOPSUN which is manufactured by Deye. It is a different model, certainly, and has a different firmware--but with the LVTOPSUN, at least, the inverter has the option to limit charging current to the battery to a user-specified amperage. I actually set mine to 20A because I am also running two EPEVER charge controllers in parallel, and want the battery limited to around 60A charge rate--so I set the two charge controllers to 20A output as well. Perhaps you have and know this is not the issue, but if you have not already done so, it may be worth checking those settings.

 

[Propalen]

@shadowmaker @kommando

I have to insist on the weakness or shadowing or heating issue. It would be an unlikely conicidence that the current stays at exact 20A when it is affected by any of these it issues. If affected by this the current will fluctuate on the external varying condition. As it exactly at specific current it is most likely an coded feature for safety purposes. Please read the link shared on first post.

@Norwasian

Thanks for your comment. At that point the battery is fully charged so all the current flows to grid. I will double check my setting anyway

 

[shadowmaker]

After looking your graphs with better time, it is indeed clipping. When combined power reaches 8kW, it starts to clip MPPT2 only.

 

[shadowmaker]

So that's why MPPT curves aren't flat during clipping, but combined power curve is.

 

[Propalen]

@shadowmaker Thanks for your comments. I have contacted DEYE support regarding the issue.



The side sticker on my inverter clearly indicating PV Input current at 26A and also Max PV Input power at 10400W. 20A is far from 26A. I will update depending on the DEYE support answers.

 

[shadowmaker]

The side sticker on my inverter clearly indicating PV Input current at 26A and also Max PV Input power at 10400W. 20A is far from 26A. I will update depending on the DEYE support answers.

AC output rated power: 8000W. It is software restricted and giving exactly what you paid for, 8kW. If you want more you should have bought 10kW or 12kW unit (which are the same unit, just different software IRC).

 

[Propalen]

@shadowmaker
That’s finally clarifying. Datasheet is clearly not well structured. My interpretation was that it will take from the grid and provide to the load a Maximum of 8kw. The it will
be able to provide 10.4kw back to the grid. What’s the purpose to be able to take a max pv 10.4 kw if you cannot feed it into the network?

What will be the next single phase hybrid model that will be able to take up 9900 pv production and feed it into the network? My thought was that the sun-8k-sg01lp1-eu was top of its family

 

[mciholas]

What’s the purpose to be able to take a max pv 10.4 kw if you cannot feed it into the network?

PV power can do two things: make AC and charge the battery.

The unit can make 8 KW AC. The rest can be used to charge the battery. If the battery doesn't need charging, then you can't use the full 10.4 KW of PV.

What will be the next single phase hybrid model that will be able to take up 9900 pv production and feed it into the network?

An inverter rated to make 10 KW AC or more.

Mike C.

 

[Propalen]

PV power can do two things: make AC and charge the battery.

The unit can make 8 KW AC. The rest can be used to charge the battery. If the battery doesn't need charging, then you can't use the full 10.4 KW of PV.


An inverter rated to make 10 KW AC or more.

Mike C.

What will be the next single phase hybrid MODEL that will be able to take up 9900 pv production and feed it into the network?

 

[shadowmaker]

What will be the next single phase hybrid MODEL that will be able to take up 9900 pv production and feed it into the network?

SUN-10K-SG02LP1-EU-AM3

But what's the point? You are "loosing" ~3kWh on a perfect day and none if the day isn't perfect. So let's assume you have 150 perfect days/year and you get 0,5$ for sold kWh. that would mean 225$ loss per year. Now put your own numbers there and recalculate. Is it really worth it?

You could also charge your batts with reduced power during morning PV off-peak and use full charge PV peak and afternoon. This way you wouldn't "loose" anything with your current setup.

Furthermore, you currently have situation called "overpaneling", which is wise because at the moment panels are cheap and inverters aren't. This way you can maximize ROI + have decent production on those less than perfect days too.

 

[Propalen]

@shadowmaker Thanks for your comments. You commented that the 10 and 12kw units are the same hw but just different software. Would it be possible to pay DEYE and upgrade the device?


After a SW update by Deye support and full sunny day, there is definitely a limitation on the max output power to around 8.2 KW.

I am wondering my options now.

1. Replace and sell current inverter. I've got a deye sun-8k-sg01lp1-eu and the suggested replacement is SUN-10K-SG02LP1-EU-AM3. My understanding from the specs is that the latter has 3 MPPTs. I would also like to undestand what the difference between SG01 and SG02 naming.

2. Accept some loss. This is just accepting some waste of installed capacity

3. Use the batteries to charge while excess power is produce. I wonder if it possible to configure this option on the inverter.

4. Sell some of the excess capacity

Any other option? Please share your suggestions on optimal solution.

 

[shadowmaker]

@shadowmaker Thanks for your comments. You commented that the 10 and 12kw units are the same hw but just different software. Would it be possible to pay DEYE and upgrade the device?


After a SW update by Deye support and full sunny day, there is definitely a limitation on the max output power to around 8.2 KW.

I am wondering my options now.

1. Replace and sell current inverter. I've got a deye sun-8k-sg01lp1-eu and the suggested replacement is SUN-10K-SG02LP1-EU-AM3. My understanding from the specs is that the latter has 3 MPPTs. I would also like to undestand what the difference between SG01 and SG02 naming.

2. Accept some loss. This is just accepting some waste of installed capacity

3. Use the batteries to charge while excess power is produce. I wonder if it possible to configure this option on the inverter.

4. Sell some of the excess capacity

Any other option? Please share your suggestions on optimal solution.

My 12Ks are 3-phase units and IRC 8/10/12 has same hardware only different software. MAYBE these can be upgraded by paying Deye. Like you said your 8kW is top of that model line, so MAYBE it can't be upgraded even paying extra.

1. Don't know difference between SG01/02, but that 10kW has indeed 3 MPPTs.

2. THIS. I mean 3kWh/good day is so little waste and you loose nothing when it's less than perfect day. Of course it depends how many good days per year and how much profit per sold kWh.

3. Using something like Home Assistant and for example 10kWh battery it would be easy to do something like this:

- Allow battery charge up to 60% between 00.00-12.00 with full charge rate. 60% of 10kWh battery means that you still have about 80Ah room left.
- Allow charge up to 100% between 12.00-16.00 but with reduced charge power (Amps limited to 20A, 4hx20A=80Ah).
- Allow charge up to 100% between 16.00-24.00 with full charge rate.

I don't have Home Assistant yet, but my friend is a nerd and he has been playing with it for few months now and has smaller, but otherwise quite similar setup than I have, so I'm hoping to copy his HA system soon.

4. If you mean panel capacity, you have only excess when it's a good day. Every bad day you'd want more panel capacity to get even some production. Up here I produced 8,1MWh last month with my setup, but only 0,5MWh in December. That's why I'm adding more panels to my system even though I already produce much more than needed in summer. It is called overpaneling and it helps when things are less than optimal.