Deye 5kw 3250W per MPPT limit and 9 panels

[RSahan]

I bought a 5KW deye to replace my Growatt SPF5000ES with 9 panels 540w in string. I have read the datasheets and manual before buying and there is no mention of the limit of 3250W per MPPT on these documents. Even the seller said 9 x 540W panels in single string would work fine. I didn't want to rewire the array to separate it to 2 strings

I just found out about this limit which is only mentioned on a sticker placed on the side of the inverter





Now I will receive the inverter in 2-3 days from China so there is no going back and I have to use it. So I decided to rewire the 9 panels to separate it to 2 strings.
I'm going to break it to 5 panels + 4 panels and I'm worried that the 4 panel string might not be enough for optimum output.


Deye MPPT range is 150-425w



My panels are rated at 39V Vmp at NOCT. JA Solar 540w. 'm in Sri lanka so the temp is 26-30c around the year.





Do you guys think 4 panels in MPPT would work fine all day optimally? 39v x 4 = 156W which is just 6v above MPPT range


Honestly If I knew this before I wouldn't have bought the Deye because now I have to spend money on rewiring, new SPD's, breakers and PV disconnect switches

Thanks in advance

 

[eriklefevre]

Hi,
I would really like to know how this playes out?
What I think is that if you would connect your 9 panel string.
It will just never produce over this 3250 Watt limit per string. I think?
Hoping that other users share if they have small strings connected.
For now I have a 6 and a 7 panel string connected.
6 is performing about the same as the 7 panel string.
I also have a Goodwe EM with 9 panels.
The new Deye is outperforming the Goodwe in low light conditions.
Deye is up 30 min before and after the Goodwe!!
Don't worry.
It is a good inverter.
Hope this helps you.

 

[RSahan]

Hi, yes if I connect everything in one string it will just work and won't produce over 3250W but then I would be wasting power because my panels are 4850W and I will atleast get 4000W at peak.

Did you take those screenshots from Deye monitoring? Why your PV1 is 76? Does it produce power at that low voltage?

 

[RSahan]

I just talked with a friend who bought the same SG03 unit as myself and he told me that his one doesn't have this sticker. Maybe this limitation is only on SG04 and SG05 models because its fanless?

 

[eriklefevre]

Hi,
Screenshots are from Homeassistant. (https://www.home-assistant.io/)
My home domotica system. My house is setup to use all excess solar using automations.
76 V was around 6:50 producing 11 watts but just starting up when screenshot was made.
So yes the 4 panel string will probebly als work fine.

 

[eriklefevre]

I just talked with a friend who bought the same SG03 unit as myself and he told me that his one doesn't have this sticker. Maybe this limitation is only on SG04 and SG05 models because its fanless?

Maybe that is the reason. I do not know.
Please ask your friend if he gets more then 3250 watt out of 1 MPPT?
I think not. But do not know.

 

[RSahan]

Maybe that is the reason. I do not know.
Please ask your friend if he gets more then 3250 watt out of 1 MPPT?
I think not. But do not know.

Unfortunately his panels are below the 3250w limit

 

[eriklefevre]

Unfortunately his panels are below the 3250w limit

Have you seen the Sunsync training videos?
I got the feeling they are more woried on the higher side of the voltage range?
The specifications let us think it is like any other inverter that should be able to handle up to 500V Voc.
The extra sticker on mine and these videos warn about using more then 450V.
What i see that the mppt's are performing really well at lower voltage.
I think that is good news for you?
Sunsync training also mentioned better not to overdemention strings!!

I am planning to change the inverter at a friends house.
He also has a 9 panel string just like you.
Do not plan (want) to rewire the 9 panel string (also 4650 Watt).
I will wait on your experiance before planing this install.
Getting the 8kw could also save us to do the rewiring i think? Hope?
And still have full potential out off this 9 panel string on the 8KW.

 

[RSahan]

9 panels in a string is within the range. My growatt inverter reports 350-400v so its perfect for Deye. I would much prefer not to split up the current string but I don't want to limit the power to 3250w either

 

[eriklefevre]

9 panels in a string is within the range. My growatt inverter reports 350-400v so its perfect for Deye. I would much prefer not to split up the current string but I don't want to limit the power to 3250w either

Yes I understand. But probebly on the 8kw the max power on 1 mppt would be higher maybe around 4000 in zero export mode. I hope? So I would advise my friends (with 1 string 4650 watt) not to go for less then 8kw inverter to avoid splitting string or losing power over 3250 watt on that string.

 

[RSahan]

I decided to first try panels in one string and see what happens and go from there. Honestly I wouldn't have bought this inverter if they advertised this in the datasheet or manual

 

[RSahan]

@eriklefevre I asked this question a month ago from Deye. This was their reply. I didn't really follow up because I didn't understand their English

 

[eriklefevre]

I decided to first try panels in one string and see what happens and go from there. Honestly I wouldn't have bought this inverter if they advertised this in the datasheet or manual

I think I would do the same.
This would not happen with other brands!!!
None off the limitations are well documented.
Like if you put inverter on Gen port. It is advised not to put more then half of the inverter power. So 6kw inverter 3kw on gen port.
I think I now this also from Sunsync training video.
Can not find 1 official Deye document about this limitation.
The deye will be more efficiant then the Growatt for your application.
I am shore off that.

 

[eriklefevre]

@eriklefevre I asked this question a month ago from Deye. This was their reply. I didn't really follow up because I didn't understand their English

View attachment 105731

Feels like they say split your string. But text is not verry helpfull.

 

[RSahan]

Ok I ended up rewiring and breaking the string to 2. 4 panels and 5 panels.
Deye MPPT starting voltage is advertised as 150V but my 4 panel string goes below that to like 146V under load but it works perfectly fine.

 

[cods4]

Ok I ended up rewiring and breaking the string to 2. 4 panels and 5 panels.
Deye MPPT starting voltage is advertised as 150V but my 4 panel string goes below that to like 146V under load but it works perfectly fine.

That's great to hear.

My 5k SG04 has the same sticker as yours. But thinking about it, it says "in zero-export application". I wonder if they literally mean this only applies if your inverter is set to not sell to the grid?

Also, the datasheets for all the 5kW inverters specify a max PV power of 6500W, which aligns with 3250W per string.

 

[eriklefevre]

That's great to hear.

My 5k SG04 has the same sticker as yours. But thinking about it, it says "in zero-export application". I wonder if they literally mean this only applies if your inverter is set to not sell to the grid?

Also, the datasheets for all the 5kW inverters specify a max PV power of 6500W, which aligns with 3250W per string.

Hi thanks for your input

My 6k SG05 has max PV power of 7800W on the label. And also 3250W per string on the warning label.
Just like your 5K model. So my warning label should say 3900W per string if your theory is correct?


I can only conclude with 4 important observations.
1) these inverter do a really good job at lower voltage PV. Even exeptional. (oversizing les important for Deye inverters)
2) documentation is about the worst on the market.
3) In off grid stiuation. The micro grid the deye creates works really verry well. (I have 3K grid tie inverter on GEN port now. Works great)
4) When connected to grid the grid consumpion should be lower!!!
My Goodwe EM did much better in avoiding grid consumption.
( as a solution i have a "1 panel micro inverter" connected before "Deye CT" when on grid. This switches to the "Deye micro grid" when I am not on-grid. To avoid losing this production and buying from Grid)

 

[cods4]

Hi thanks for your input

My 6k SG05 has max PV power of 7800W on the label. And also 3250W per string on the warning label.
Just like your 5K model. So my warning label should say 3900W per string if your theory is correct?

That makes so sense does it? The 6k only has 2 MPPTs right, so if you follow that label, you can't use the full rating of the inverter (6kw to load, and 1.8kw to battery at the same time). Surely they didn't think that through. Or who ever put the labels on, pulled one out of the wrong stack.

I can only conclude with 4 important observations.
1) these inverter do a really good job at lower voltage PV. Even exeptional. (oversizing les important for Deye inverters)
2) documentation is about the worst on the market.
3) In off grid stiuation. The micro grid the deye creates works really verry well. (I have 3K grid tie inverter on GEN port now. Works great)
4) When connected to grid the grid consumpion should be lower!!!
My Goodwe EM did much better in avoiding grid consumption.
( as a solution i have a "1 panel micro inverter" connected before "Deye CT" when on grid. This switches to the "Deye micro grid" when I am not on-grid. To avoid losing this production and buying from Grid)

My system isn't quite commissioned, but i was a little worried that my strings (6 strings of 6 panels each) wouldn't be in the ideal voltage range (Voc min is around 246V). But sounds like that's not a concern at all.

Agreed, documentation isn't great, it helps that you can read through the Sunsynk documentation and watch Keith's videos to get another point of view, but it can still be confusing.

And support is very responsive and tries their best. But the language barrier makes it a pretty average experience.

Regarding grid consumption, are you in a zero export situation? You can adjust the 'zero-export power'. Have you had a play with that setting?

 

[eriklefevre]

That makes so sense does it? The 6k only has 2 MPPTs right, so if you follow that label, you can't use the full rating of the inverter (6kw to load, and 1.8kw to battery at the same time). Surely they didn't think that through. Or who ever put the labels on, pulled one out of the wrong stack.


My system isn't quite commissioned, but i was a little worried that my strings (6 strings of 6 panels each) wouldn't be in the ideal voltage range (Voc min is around 246V). But sounds like that's not a concern at all.

Agreed, documentation isn't great, it helps that you can read through the Sunsynk documentation and watch Keith's videos to get another point of view, but it can still be confusing.

And support is very responsive and tries their best. But the language barrier makes it a pretty average experience.

Regarding grid consumption, are you in a zero export situation? You can adjust the 'zero-export power'. Have you had a play with that setting?

Hello,
I have tried all versions off grid connection even also the "selling first" and adjusting zero export power to 0 and 20 even 100 Watt. First 3 weeks i had the Deye every day differant settings. Best result for 1 day Goodwe EM was 0,4 kwh (befor Deye) and for the Deye (now) it was 0,6 kwh. I understand that this is not a lot but 9 monts a year I don't really need the grid and hate paying for any grid power. I do not get fined nor payed for export power. Once the battery is 100%. The Deye is also doing fine. Just not when charging from solar. This is when it is not so good. Maybe also important that when the Goodwe was set to a (any) export limitation. It was also very bad. But on that install I limited the solar array of the EM and added a second grid tie inverter with a limiter set. Then all was working perfect.

I want to document the final install i do with this 6K Deye to share the results.
But for know I am still not 100% ready. I know i can still make it better.

I have 2 string 7X450Watt connected to Deye.
1 string 8X450wat to a Goodwe XS on Gen port.
1x 450watt panel on cheap micro inverter that can switch between grid an Gen port.
So total 23x 450 watt JA solar panels.
I only go ongrid for the time the jacuzzi pumps are at full blast.
The 6kw Deye can't allways handle that surge off power needed at start up.
When on grid now the micro inverter is keeping import to actual Zero.

And yes Deye support was a good experiance. Just language.

 

[eriklefevre]

That makes so sense does it? The 6k only has 2 MPPTs right, so if you follow that label, you can't use the full rating of the inverter (6kw to load, and 1.8kw to battery at the same time). Surely they didn't think that through. Or who ever put the labels on, pulled one out of the wrong stack.

I have tested this with the Goodwe EM. About 6300Watt pv installed. 2 string 8x450=6300watt. EM Charger is max 50amp/2,4kw running at 1,3kw and suplying to 5kw louds at same time. So total was really 6300 watt and the EM could go up to 6600 with more panels. 6600 is the limit of the EM. So 5K + 1,6K charging at same time. Test results proof this.

In some scenario this would an could be possible 6kw and 1,8kw to battery.(6K Deye)
I think if yo can export all excess you can do this and it would work great with any hybride inverter system.

I have also thought that my 3250Watt label maybe for a 5K deye like you say.
I hope some day to be shore about this!!!! Any one has a 6 k Deye please let me know? If your label is 3250 limit or more?