Typicall all in one (MPP/Growatt/etc) - can it provide output from battery pack and AC/DC converter simultaneously?

[rajseth]

I want to use a 6500W all-in-one to provide surge power to a planned off grid cabin - Solar with a 2000W(1600 continuous) Honda gen as backup. If I use a separate charger driven by the generator, and run the inverter from the battery/charger setup - the batteries will act as an energy capacitor, charging while inverter draw is below charger input, and discharging when power demand surges.

Can an All-in-one do the same? Or do they work like an inverter charger - either charging or inverting - but not both simultaneously? Am I just best off using the AIMS 36/48V Charger (1000W) direct to the battery without the all-in-one "knowing" about it? I do expect daily demand to be below 12-14 kWH so easily handled by the generator / charger combination. If the sun shines during the day, I am alright because I intend to waaaaay overbuild the on ground solar array in a nearby clearing.

 

[DThames]

I have a couple of Growatt 3000 units. Inside each has an AC charger, solar charger, and an inverter that is powered by the battery. The inverter basically runs off of the battery and the chargers keep the battery charged within their limits, verses the inverter load. Hope that helps.

So yes, you could be charging at 1600w continuous (as long as the battery needs charged) and also loading the inverter (even to the inverter's max).

 

[rajseth]

Thanks DThames - let me understand and double check - Set #01 as SBU, #11 as 25A, #14 as SNU, and if night time, and generator is hooked up, the unit will use 25A DC power from the charger output & the batteries to power the inverter. This is distinct from inverter chargers - which choose either battery or ac input, but not both, to the ac output.

Setup - 2x3000W Growatt 48V SPF 3000TL LVM in parallel, 16 cell 280Ah pack (14kWH) and a big solar array
Does anyone know if the MPP all in one units will do the same?

 

[12VoltInstalls]

Does anyone know if the MPP all in one units will do the same?

The 1012LV-MK can charge the batteries and/or pass through grid all depending on how you set it up

 

[rajseth]

I heard from Ian @ watts247. His reply.
"Mpp or growatt. The same result.
3500W draw on a 6kw inverter, the battery will have to supply it,
If battery runs low and switches to Ac input, the 1500W generator week be unable to supply 3500W, so the system at some point will shut down .
It can't share battery abs AC power at the same time. It's one or the other.
Ian"

That is what I was afraid of. So I will have to direct charge the battery outside the all-in-one'e purview

 

[12VoltInstalls]

That is what I was afraid of.

Perhaps I’m misunderstanding the programming options?

 

[RCinFLA]

What you are looking for is normally called 'load shaving'.

I don't believe Growatt HF inverter or most of the Chinese HF inverters will do this. It does not mention anything like this in user manual. Closest related info is statements on setup 01.

"Utility will provide power to the loads as first priority.
Solar and battery energy will provide power to the loads only when utility power is not available."

"Solar energy provides power to the loads as first priority. If solar energy is not sufficient to power all connected loads, solar and utility will power loads at the same time. Battery provides power to the loads only when solar energy is not sufficient and there is no utility."

Many Chinese HF inverters' battery to HV DC converters are not truly bi-directional. They have a separate HV DC-DC buck converter function that uses the forward converter series inductor to charge battery. These means they have to stop forward power converter and switch over to buck converter operation to charge battery. This is not instantaneous which prevents a unit on AC input with AC pass-through and AC battery charging active to immediately stop charging and source AC output when AC input current limit is exceeded by external AC pass-through loads.

Any hybrid inverter with 'load shaving' capability will have a user setup for 'Max AC input current' which sets the point where load shaving by inverter starts to happen.

Best bet for load shaving option is low frequency inverters, but not all of them have the firmware to provide the function.

 

[DThames]

I want to use a 6500W all-in-one to provide surge power to a planned off grid cabin - Solar with a 2000W(1600 continuous) Honda gen as backup. If I use a separate charger driven by the generator, and run the inverter from the battery/charger setup - the batteries will act as an energy capacitor, charging while inverter draw is below charger input, and discharging when power demand surges.

Can an All-in-one do the same? Or do they work like an inverter charger - either charging or inverting - but not both simultaneously? Am I just best off using the AIMS 36/48V Charger (1000W) direct to the battery without the all-in-one "knowing" about it? I do expect daily demand to be below 12-14 kWH so easily handled by the generator / charger combination. If the sun shines during the day, I am alright because I intend to waaaaay overbuild the on ground solar array in a nearby clearing.

Have you purchased the inverter yet?

 

[rajseth]

Nope - haven't purchased diddly. Have time to think this through first
I did purchase couple overkill solar BMSs last year (4s 120A & 8s 100A) but got the shaft from Michael Caro on batteries so the BMSs are sitting idle, NIB.
Now I am thinking to unbundle, use a Giandel 3000W24V inverter, Aims 24V charger, and Victron MPPT controller to make my own package. That will be able to parallel the DC sources into the battery bank, while the inverter will make Juice as needed

 

[houseofancients]

What you are looking for is normally called 'load shaving'.

I don't believe Growatt HF inverter or most of the Chinese HF inverters will do this. It does not mention anything like this in user manual. Closest related info is statements on setup 01.

"Utility will provide power to the loads as first priority.
Solar and battery energy will provide power to the loads only when utility power is not available."

"Solar energy provides power to the loads as first priority. If solar energy is not sufficient to power all connected loads, solar and utility will power loads at the same time. Battery provides power to the loads only when solar energy is not sufficient and there is no utility."

Many Chinese HF inverters' battery to HV DC converters are not truly bi-directional. They have a separate HV DC-DC buck converter function that uses the forward converter series inductor to charge battery. These means they have to stop forward power converter and switch over to buck converter operation to charge battery. This is not instantaneous which prevents a unit on AC input with AC pass-through and AC battery charging active to immediately stop charging and source AC output when AC input current limit is exceeded by external AC pass-through loads.

Any hybrid inverter with 'load shaving' capability will have a user setup for 'Max AC input current' which sets the point where load shaving by inverter starts to happen.

Best bet for load shaving option is low frequency inverters, but not all of them have the firmware to provide the function.

deye/sunsynk/sol-ark are among the few that can

 

[madmax]

I like load shaving in theory, only because it would allow my small generator to power even large loads.
Fortunately, the chances of me using it that way are small. Thus I just use my it in the dumber way (plug my all in one direct to generator and set a low charge rate. )

 

[DThames]

Nope - haven't purchased diddly. Have time to think this through first
I did purchase couple overkill solar BMSs last year (4s 120A & 8s 100A) but got the shaft from Michael Caro on batteries so the BMSa are sitting idle, NIB.
Now I am thinking to unbundle, use a Giandel 3000W24V inverter, Aims 24V charger, and Victron MPPT controller to make my own package. That will be able to parallel the DC sources into the battery bank, while the inverter will make Juice as needed

I am going to try to explain something that I have a limited understanding of but it is a good topic to explore and to understand. Some of the terms, I sort of made up so as to describe them.

Imagine the design challenges to charge off the grid, use of the grid, charge off of solar, use off of solar, and use off the battery in all possible mixed modes.

Example 1, battery based inverters, 48v battery.
You need a step down charger for grid charging and a step down PV charger for higher PV volts charging. You also need a step up converter to bring the 48v up to 180v-200v DC (InverterDCBus) for the inverter to make 120v AC. If you want to pull some power from the grid, you would need something to charge the InverterDCBus from the 120v input, so the inverter could draw power from the grid. If you want to use power directly from solar panels, you need to charge or pass power to the InverterDCBus from the PV input.
So in this example, all power to the inverter comes from the battery. All power coming "in" goes through some charging circuit to the battery.

Example 2, Inverter BUS based inverter, 48v battery.
The inverter is powered from the InverterDCBus. A "charger" from the battery can add power to the InverterDCBus. A charger from the grid can add power to the InverterDCBUS. A charger from PV input can add power to the InverterDCBUS. if the battery needs charged, a step down charger will charge the battery from the InverterDCBUS.
So in this example, there is only one battery charger. All power "in" goes to the InverterDCBUS. This opens more doors for power consumption by the inverter.

Example 3, Inverter BUS based inverter, 300v battery.
This example would be very similar to example 2 but with a battery voltage somewhere around the PV input voltage. Less stepdown or stepup between the battery voltage and the InverterDCBus is needed. These appear to be the trend but need special higher voltage batteries.

Look at the Phocos Any-grid videos. 1 of 3. The Phocos is example #2.