EG4 3000 (Generator to the AC In or the DC In?)

[50ShadesOfDirt]

Some AIO's have restrictions on generators as shore power (vs the grid), because they want to sync with the incoming electric power source, and provide "0ms time switchover". There is one MPP Solar unit that has this restriction in their manual for that model ... could be some/many other AIO's with similar restrictions, as only a few manufacturers for all the brands.

You'll need to read the manual for your inverter, and see if perhaps the same restriction applies ...

They'll let you feed in "grid power", but not gen power, not even inverter-gen ...

You may have to switch to something like a chargeverter (48v only at this time), and charge the battery-bank directly. Or come up with your own charging scheme involving your generator charging the battery-bank.

Hope this helps ...

 

[MikeRI]

References please.

This video provides a good explanation of the problem (start 30 seconds in).

 

[MikeRI]

I wound up trying to charge with the generator connected to the inverter's 'AC IN' while under load, and the EG4 3000 did not like it at all; it threw an error message. But when I disconnected the inverter from the load it charged fine, with the inverter's AC IN capped at 10 amps. BUT, I want to run the generator with the inverter under load, so the home can have power while the batteries are being charged by the generator. Gonna try a Plan B (not sure what it'll be at this point). It seems the Chargeverter -- or something else that will charge the batteries directly -- is the easiest and best route to go.

 

[Vigo]

BUT, I want to run the generator with the inverter under load, so the home can have power while the batteries are being charged by the generator.

That is fine, as long as your load wattage is less than your charging wattage!

Since you are about to add another layer of energy conversions (from 120vac to 48vdc for example) there will be losses to account for. So if you have a 2000 watt generator and run an 85% efficient charger off of it, you may only get 1700w of charging and have to keep your power consumption under 1700w or else you'll be at a 'net loss' and be draining your batteries by however much over 1700w your loads are. You may already fully grasp this but im pointing it out anyway just to be safe. In my small home i found that i could more or less live normally with about 2500w of charging because even if i did require some ac or heat, or even run my electric drier, those things 'cycle' on/off and it averaged out to less than 2500w, so i was able to break even or charge a bit even with only 2500w in even though my consumption would sometimes go over 5000w for brief periods.

 

[MacKiller]

I ran into this thread, because I wanted to do exactly what the OP was thinking of doing (using the PV ports for generator power) for two reasons:
1. I want the full integration of the AIO system, including correct energy reporting and intelligent charging/energy usage.
2. If my house runs out of power, I don't want to disconnect the grid by hand and plug something else in. I want a super easy to use system that I can teach the usage to others (non-techies).
@MikeRI, what did you end up doing?
@Vigo, would you mind sharing a little more of the setup you've used?
Thanks!

 

[DIYrich]

There are threads on why it is a bad idea to hook up anything but solar to the mppt connection. One exception may be if the power exceeds the mppt power.

If you are going to convert the generator power to dc, then just charge the battery directly.

 

[MacKiller]

There are threads on why it is a bad idea to hook up anything but solar to the mppt connection. One exception may be if the power exceeds the mppt power.

If you are going to convert the generator power to dc, then just charge the battery directly.

Thanks @DIYrich! I would love to learn more on the subject. I’ve been looking, but hard to find. Do you by chance recall a few of those threads? Also, is there a way to fulfill requirements 1 and 2 above? The only one I saw so far that may do that was the 15kw Sol-Ark with the Gen pinout and that was kind of steep at $7k.

 

[DIYrich]

Thanks @DIYrich! I would love to learn more on the subject. I’ve been looking, but hard to find. Do you by chance recall a few of those threads?

Search for "Power Supply MPPT" or "Generator MPPT". One thread with an explanation of the problem is:

Feeding 48v, stepped up from 12v battery, intopower station MPPT SCC input?

Thought this was best place to ask about issues on burning out a power station input. Moved it here. I want to use a 12v 100Ah LiFePO4 battery to feed my power station, thus increasing its capacity a bit. I have a Pecron e1500LFP, it has a 32-95v 700W input for mppt solar charge controller...

diysolarforum.com

Also, is there a way to fulfill requirements 1 and 2 above? The only one I saw so far that may do that was the 15kw Sol-Ark with the Gen pinout and that was kind of steep at $7k.

EG4 18kpv is similar to the Sol-Ark 15k. The 18kpv has some growing pains (see thread on 400v problem). The soon to be available Growatt sph-10000tl-hu-us is also worth looking at.

If you don't want to export to grid, the EG4 6000xp.

 

[MacKiller]

Search for "Power Supply MPPT" or "Generator MPPT". One thread with an explanation of the problem is:

Feeding 48v, stepped up from 12v battery, intopower station MPPT SCC input?

Thought this was best place to ask about issues on burning out a power station input. Moved it here. I want to use a 12v 100Ah LiFePO4 battery to feed my power station, thus increasing its capacity a bit. I have a Pecron e1500LFP, it has a 32-95v 700W input for mppt solar charge controller...

diysolarforum.com

EG4 18kpv is similar to the Sol-Ark 15k. The 18kpv has some growing pains (see thread on 400v problem). The soon to be available Growatt sph-10000tl-hu-us is also worth looking at.

If you don't want to export to grid, the EG4 6000xp.

The whole answer was very helpful, thanks! That thread particularly clarified how the MPPT will try to modulate the voltage and the dangers of that. So close, but not quite there yet! The solutions seem to be getting closer to a true AIO solution that can report utilization, fully manage the charging/usage, use a generator without intervention, and not break the bank...