How to select a second hybrid inverter

Moxi
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How to select a second hybrid inverter

#1

Post by Moxi »

Is there any secret to selecting a second hybrid inverter to run in parallel to your main hybrid inverter ? What do you need to look out for in terms of compatibility?

I recall there being a few discussions about this sort of thing but couldn’t find any when I went looking earlier.

I only want something to handle an extra 2kWp dc and ideally it will be programmable for a set maximum discharge to stay within the terms of the current set up eg 3.6kW max export.

My hybrid is an ac coupled Solis 3.6kW

Moxi
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Stinsy
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Re: How to select a second hybrid inverter

#2

Post by Stinsy »

Moxi wrote: Thu Nov 21, 2024 6:46 pm Is there any secret to selecting a second hybrid inverter to run in parallel to your main hybrid inverter ? What do you need to look out for in terms of compatibility?

I recall there being a few discussions about this sort of thing but couldn’t find any when I went looking earlier.

I only want something to handle an extra 2kWp dc and ideally it will be programmable for a set maximum discharge to stay within the terms of the current set up eg 3.6kW max export.

My hybrid is an ac coupled Solis 3.6kW

Moxi
Depends what you want to achieve!

Smart or dumb?

If you just want to assist the charge and force discharge at the same time your main inverter then you’re golden. If you want the two to work together to match your consumption then people have found this challenging (you can end up with one inverter charging at full whack while the other discharges).

The easy option is to sell your current inverter and buy a bigger replacement…
12x 340W JA Solar panels (4.08kWp)
3x 380W JA Solar panels (1.14kWp)
5x 2.4kWh Pylontech batteries (12kWh)
LuxPower inverter/charger

(Artist formally known as ******, well it should be obvious enough to those for whom such things are important.)
Moxi
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Re: How to select a second hybrid inverter

#3

Post by Moxi »

The second option leaves me AC tied and I was hoping to take advantage of some dc charging now that I have more scope for extra panels

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nowty
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Re: How to select a second hybrid inverter

#4

Post by nowty »

You can still DC charge your battery bank with separate DC charge controllers even if they are connected to an AC grid tie inverter, some of us do that.
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 27MWh generated
6 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 520 m3
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Joeboy
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Re: How to select a second hybrid inverter

#5

Post by Joeboy »

nowty wrote: Thu Nov 21, 2024 11:17 pm You can still DC charge your battery bank with separate DC charge controllers even if they are connected to an AC grid tie inverter, some of us do that.
Like this? :lol:
Image
15kW PV SE, VI, HM, EN
42kWh LFPO4 storage
7kW ASHP
200ltr HWT.
73kWh HI5
Deep insulation, air leak ct'd home
WBSx2
Low energy bulbs
Veg patches & fruit trees
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Stinsy
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Re: How to select a second hybrid inverter

#6

Post by Stinsy »

I don’t understand your challenge with being AC tied.

If you want to achieve adding more solar then a charge controller is a good solution. It won’t affect how fast you can charge your batteries from the grid, or how much power you can supply at a particular moment and you might find your batteries fill faster than you can use the electric on sunny days.
12x 340W JA Solar panels (4.08kWp)
3x 380W JA Solar panels (1.14kWp)
5x 2.4kWh Pylontech batteries (12kWh)
LuxPower inverter/charger

(Artist formally known as ******, well it should be obvious enough to those for whom such things are important.)
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nowty
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Re: How to select a second hybrid inverter

#7

Post by nowty »

Joeboy wrote: Fri Nov 22, 2024 3:58 am
nowty wrote: Thu Nov 21, 2024 11:17 pm You can still DC charge your battery bank with separate DC charge controllers even if they are connected to an AC grid tie inverter, some of us do that.
Like this? :lol:
Image
Aye.
Image
18.7kW PV > 109MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 27MWh generated
6 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 520 m3
Moxi
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Joined: Sun Oct 31, 2021 3:46 pm

Re: How to select a second hybrid inverter

#8

Post by Moxi »

Thanks, I’m guilty of over thinking this particular problem I think

Moxi
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Joeboy
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Re: How to select a second hybrid inverter

#9

Post by Joeboy »

Moxi wrote: Fri Nov 22, 2024 12:26 pm Thanks, I’m guilty of over thinking this particular problem I think

Moxi
Could futureproof too?

https://camelot-forum.co.uk/phpBB3/view ... =26&t=3488
15kW PV SE, VI, HM, EN
42kWh LFPO4 storage
7kW ASHP
200ltr HWT.
73kWh HI5
Deep insulation, air leak ct'd home
WBSx2
Low energy bulbs
Veg patches & fruit trees
MrPablo
Posts: 286
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Re: How to select a second hybrid inverter

#10

Post by MrPablo »

If 3.6kW AC output is enough for you then I'd recommend DC coupling. It's just easier to expand overtime as needed.

If you want more AC output to support house loads then I would recommend upsizing from your existing Solis.
They aren't the smartest units out of the box, and if there's another AC inverter then they can oscillate AC output at times.

A friend took my old 3.6kW Solis and I ended up installing another modbus meter that recorded output from his existing SMA PV inverter.
Without that, it just didn't handle low load, low PV well at all.

I guess the question is, how much AC output do you need in total?
10x 405W JA Solar panels (4.05kWp) @ 5 degrees
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
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