Small solar advice (5KVA hybrid system)

denmendez65 said:
I think you misunderstood me.

When PV is low, the fancy inverters will blend grid and Pv. Battery stays full.


Axpert will blend battery and PV.

If battery cut off is hit during the day and the MPPT is still on, Axpert will switch to grid and supply load with 100% grid but the PV that is still coming in is used by the inverter to charge the batteries. If the MPPT switches off due to low light then it will finish off the charging with the grid. The fancy inverter during the time the Axpert was running off the battery was using the grid and PV until the PV is gone and then it uses PV and battery. But the same Pv used by it is the same one used by the Axpert. Only difference is the battery stayed full throughout.
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where do you get this info from?
why would the battery stay full you still using the battery - It will always blend battery and PV it will only Supplement with Grid if the combination of PV and battery is not sufficient - axpert would do the same only it wont blend grid it will use all grid for the load and swap the PC to only charge the battery

denmendez65 said:
But at no point is the Pv wasted.
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if you set it not to use battery (or no battery) it would be wasted - on an inverter that can blend it will use both PV and Grid - an Axpert will lose the PV
not sure why a person wil not want to use battery but some people be special
denmendez65 said:
Basically the kWh used by both inverters from the Sun and Grid is the same. Maybe difference is the efficiencies. It’s just a difference of appproach that’s all.

Blending to me is fancy Jargon used by manufacturers to say heir inverter is better than the other brand but when you go into details there really isn’t much difference
Click to expand...
Efficiency might be a reason - it swiches less
 
isie said:
where do you get this info from?
why would the battery stay full you still using the battery - It will always blend battery and PV it will only Supplement with Grid if the combination of PV and battery is not sufficient - axpert would do the same only it wont blend grid it will use all grid for the load and swap the PC to only charge the battery


if you set it not to use battery (or no battery) it would be wasted - on an inverter that can blend it will use both PV and Grid - an Axpert will lose the PV
not sure why a person wil not want to use battery but some people be special

Efficiency might be a reason - it swiches less
Click to expand...
Well it would be logical that if an inverter blends grid and PV together the battery would stay full? Maybe I am mistaken in that regard. Is it a ratio you set maybe? Grid, PV and battery to meet the load requirements? I assumed it would be grid and PV only.

On my inverter It will always use the battery no matter what and will always use the PV. So it cant under utilize the PV as long as there is a battery or load. Might be Axpert type dependent as we have seen now that they arent all the same.
 
denmendez65 said:
Well it would be logical that if an inverter blends grid and PV together the battery would stay full?
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it only blends when it needs to - same reason axpert will only swap to grid when it needs
denmendez65 said:
Maybe I am mistaken in that regard. Is it a ratio you set maybe? Grid, PV and battery to meet the load requirements? I assumed it would be grid and PV only.


On my inverter It will always use the battery no matter what and will always use the PV. So it cant under utilize the PV as long as there is a battery or load. Might be Axpert type dependent as we have seen now that they arent all the same.
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If i remember the settings on the axpert you would set this based on a battery voltage and the more modern ones SOC% or DOD%
its the same on our inverters.
its what they do when that limit is reached is different
 
Another question, I see the Deye 5kw says 3250w per MPPT for the 5kw but 6 x 585w panels are over that so I assume it would need to be split over the 2 instead.

Does this make a difference and in what way? Should it be split equally 3 and 3?
 
NR7 said:
Another question, I see the Deye 5kw says 3250w per MPPT for the 5kw but 6 x 585w panels are over that so I assume it would need to be split over the 2 instead.

Does this make a difference and in what way? Should it be split equally 3 and 3?
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You can overspec mppts, gives better performance in cloudy conditions. Rule is the string voltage must not max out mppt max voltage and then on top of that you need to give a 10-20% buffer for cold conditions when panel voltages increase. Mppts can clip the amps.

So take voc number of panel and times by 6 and see if you have a buffer.
 
NR7 said:
Another question, I see the Deye 5kw says 3250w per MPPT for the 5kw but 6 x 585w panels are over that so I assume it would need to be split over the 2 instead.

Does this make a difference and in what way? Should it be split equally 3 and 3?
Click to expand...
What @wingnut771 said.

I am 500W over the spec of mine. My VOC for the inverter is 360V. But my 7 panels on the string do 300V. Perfectly safe.
 
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denmendez65 said:
What @wingnut771 said.

I am 500W over the spec of mine. My VOC for the inverter is 360V. But my 7 panels on the string do 300V. Perfectly safe.
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You can work out the voltage increase by the temp coefficient spec on the panel. You take historical low for your area, lets say -2c, then subtract 27 (25c (std temp panel is rated at) to -2c) times pmax coefficient percent:
1776343528881.png
www.solarquotes.com.au

Pmax And NOCT: How Solar Panels Perform In The Heat

The hotter it gets the worse solar panels perform. Discover what Pmax & NOCT are and how they show you which solar panels are best at handling heat.
www.solarquotes.com.au www.solarquotes.com.au
 
wingnut771 said:
You can work out the voltage increase by the temp coefficient spec on the panel. You take historical low for your area, lets say -2c, then subtract 27 (25c (std temp panel is rated at) to -2c) times pmax coefficient percent:
View attachment 1901397
www.solarquotes.com.au

Pmax And NOCT: How Solar Panels Perform In The Heat

The hotter it gets the worse solar panels perform. Discover what Pmax & NOCT are and how they show you which solar panels are best at handling heat.
www.solarquotes.com.au www.solarquotes.com.au
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I will be honest, I just thumb-sucked and couldn't put the 8th panel on the inverter as it would hit around 345V. My max operating MPPT voltage is 320V. Open circuit is 360. My panels operate at 300V.
 
NR7 said:
Another question, I see the Deye 5kw says 3250w per MPPT for the 5kw but 6 x 585w panels are over that so I assume it would need to be split over the 2 instead.

Does this make a difference and in what way? Should it be split equally 3 and 3?
Click to expand...
What everyone else said, but also, you can run them parrallel.
I have 2x luxpower 5kw inverters (2 mppt channels per inverter) with 12 panels.
6 panels each inverter, but not 3 to each mppt, instead the 2 mppt are linked in parrallel, so they do equal load.
 
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Zuner said:
What everyone else said, but also, you can run them parrallel.
I have 2x luxpower 5kw inverters (2 mppt channels per inverter) with 12 panels.
6 panels each inverter, but not 3 to each mppt, instead the 2 mppt are linked in parrallel, so they do equal load.
Click to expand...
I actually could have overpanelled by 1500W if I got the same panels that are on my geyser. They are 340W and 9A output.

Could have done 8 in series and paralleled that string with another 8 in series. My inverters input is rated for 18A so it would clip he current rarely. Would just help more in cloudy conditions but I would still be limited to a Max of 4000W rather than the 5500 i could have had. Despite my 4550 installed I dont see over the 4000 that its rated for. Stops at exactly 3990W.
 
NR7 said:
Hi,

Looking at a small 5KVA hybrid solar system for my folks essentials.

Was looking at a Deye 5KVA hybrid inverter with a 5.12KWH Deye battery and 6 x 500ish panels on a zinc roof.
Installer recommended to consider a Luxpower hybrid inverter instead to keep costs more reasonable.

They are quite happy to continue with municipal power especially since loadshedding has reduced, however the practicality of powering the essentials without having to waste petrol on the current generator is attractive.

Advice?
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Having installed both, I would rather go for the Deye. Luxpower has an overly-complicated software that just frustrates me. Also, I found the Luxpower to be louder than the Deye. In my opinion the app of Deye is better too.
Others may disagree, but I would not want a Luxpower, even if I got it for free.
 
denmendez65 said:
I actually could have overpanelled by 1500W if I got the same panels that are on my geyser. They are 340W and 9A output.

Could have done 8 in series and paralleled that string with another 8 in series. My inverters input is rated for 18A so it would clip he current rarely. Would just help more in cloudy conditions but I would still be limited to a Max of 4000W rather than the 5500 i could have had. Despite my 4550 installed I dont see over the 4000 that its rated for. Stops at exactly 3990W.
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My panels are rated for 6780wp
2 strings of 6 panels, which them go into 2 mppt in parrallel, so panels aren't parrallel mppt are.

I have seen over 8kw before, when everything is cool on rainy days and the sun suddenly comes out it sustains over 7.5kw before everything warms up.

1776348476820.png

1776348507488.png
 
Zuner said:
My panels are rated for 6780wp
2 strings of 6 panels, which them go into 2 mppt in parrallel, so panels aren't parrallel mppt are.

I have seen over 8kw before, when everything is cool on rainy days and the sun suddenly comes out it sustains over 7.5kw before everything warms up.

View attachment 1901414

View attachment 1901415
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If 2 strings are paralleled to one MPPT input, the inverter shouldn't care. Must just have Fuses on both.
 
Solarphile said:
Having installed both, I would rather go for the Deye. Luxpower has an overly-complicated software that just frustrates me. Also, I found the Luxpower to be louder than the Deye. In my opinion the app of Deye is better too.
Others may disagree, but I would not want a Luxpower, even if I got it for free.
Click to expand...
lol harsh, I don't find it complicated, could most certainly be better but it works.
there have been firmware updates, the 2 inverters are in the garage shared wall to my lounge, i.e they are mount literally behind me when sitting on the couch, and I don't hear them even a little.

10kw (2x5kw) run the entire house, entire DB is connected to the inverter output.
 
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