Can this inverter be used off grid?

[Robbo123]

Hi,
can this inverter be used off grid? I will have 18kwh lithium but I’m told by someone it cannot be used. It also can’t be used on grid as it no longer on the approved list in Australia to be grid tied.
already put a deposit on it so can someone please confirm. I intended it for purely offgrid use.
ABB 3 phase 28kw; :TRIO-27.6-TL-OUTD-400;

[inetdog]

That model is strictly a grid-interactive inverter, and even if that could somehow be accommodated, the MPPT DC inputs are not suitable for input from a battery (voltage device) instead of a PV string (constant current).

[Salts]

Inverters come in two MAJOR types.. Solar Inverters and Battery Inverters. Your ABB inverter is a Solar Inverter. It is designed to be hooked up to solar panels and convert the DC power coming from them into AC power.

You could use it in an off-grid setup through AC Coupling, but you'd still have to have solar panels powering it. You could set up ac coupling by hooking your batteries up to an AC Coupled battery inverter, which would then make AC power from the battery juice. This AC power would then cause the ABB inverter to think the grid is working and it would then start making power as well.

This is how my system works. Lithium Ion battery salvaged from a car, powering a couple of Sunny Island inverters. When the grid goes down, the Sunny Islands start drawing juice from the batteries.. the (normally) grid-tied solar inverter see's this grid quality power and think the grid is still active so it makes power (AC) as well.

If the solar array makes more power than the house uses, the Sunny Islands use the extra juice to charge the batteries. If the array doesn't make enough, the Sunny Islands draw from the batteries to make up for the deficit.

Got to test it the other day when a big stormed knocked out 500k people in Michigan, I was in awe of how well it worked.

[Robbo123]

Everywhere I turn the advice is conflicting. I’ll err on the side of caution and not buy it. Thanks all

[Salts]

Everywhere I turn the advice is conflicting. I’ll err on the side of caution and not buy it. Thanks all

My advice is accurate. Almost any Grid Tied inverter can be used off grid but it takes extra equipment to make it work.. and that extra equipment is not cheap.

If you tell us what you're trying to do, I can point you in the right direction.

That inverter you're asking about is a 3 phase unit. It is not designed to be used off grid, even though it could be.. And more importantly, it is NOT designed to provide household power. That inverter is designed for commercial and industrial buildings and large solar installations.

What are you trying to do?

[Robbo123]

Thanks. I’m trying to go offgrid, with 16S 375ah LifePo4 batteries (3.2v) for ~18kwh of storage.
wanted 3 phase to run large equip in large shed. Building house in a few years too. Prepared to put 40kw+ of panels up. I’ll be growing vertically farmed veges in shed smallish scale at some point too using leds so want excess power and don’t want to ever need to upgrade.

[Salts]

Thanks. I’m trying to go offgrid, with 16S 375ah LifePo4 batteries (3.2v) for ~18kwh of storage.
wanted 3 phase to run large equip in large shed. Building house in a few years too. Prepared to put 40kw+ of panels up. I’ll be growing vertically farmed veges in shed smallish scale at some point too using leds so want excess power and don’t want to ever need to upgrade.

If you have the money, you could put up a bank of SMA Sunny Island 6048 battery inverters and configure them for 3 phase operation. That would give you 18,000 watts of power (3 x 6000 watts) continuous. I think you can even stack two of them (or more) on each leg of the 3 phase system for double that...

Then its just a matter of putting up your solar array and harvesting the power. To that end:
OPTION 1 - You could purchase that three phase ABB inverter (or any 3 phase MPPT Grid Tied inverter) and the Sunny Islands will AC Couple to it.
OPTION 2 - You purchase normal DC Charge Controllers which take the power from your panels and use it to charge the batteries directly. You would most likely need several of them, which would also provide a bit of redundancy if one ever failed.

I went with the AC Coupling option because its more efficient in my situation and allows me to feed power to the utility grid when I'm not using the off-grid system. My solar operates like almost all other residential solar installations feeding power to the grid when the grid is available. Its not until the grid goes down that the system becomes an AC Coupled off-grid array.

One other thing.. 40kw of panels is a lot of power for an 18kw battery bank. You'll probably want to double or triple that.