Parallel systems

Question

question

Aric asked Mar 3, '24

Parallel systems

Looking for Inverters in the 3kw range to connect the solar system from an rv to the system in an off grid cabin. Looking at a parallel Inverter configuration that I can combine the two systems together when there.

I would like to combine the two inverters from the systems in parallel keeping 120v, making enough power to run larger 120v loads like air conditioning and for longer periods of time. Thinking the parallel configuration would utilize both battery banks as well as combine Inverter wattage.

multiple inverters

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Modifications Space

Node Red Space

Answer 1 · 2024-03-03T17:38:17Z

nickdb answered · Mar 03 at 05:38 PM

If you mean paralleling an inverter in an rv to another at home? That won’t work.

Installation requirements are strict for it to work, and it is not designed for that use case.

They also have to share one battery bank.

Rather look at cascading systems. It isn’t ideal or supported but is the close you will get.

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Answer 2 · 2024-03-03T17:38:36Z

Alexandra answered · Mar 03 at 05:38 PM

@Aric

There is no way really to have a parrallel system only some times. The wiring and programming alone would make that a pain.

What you might be able to do is power assist one of the other (as in one it the grid input for the other), but this is not a supported use by Victron.

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Answer 3 · 2024-03-03T17:45:20Z

delf67 answered · Mar 03 at 05:45 PM

Posts crossed with Alexandra and Nickdb. I just can't type fast enough!

Unfortunately, it won't be as simple as rocking up, plugging in and combining the two systems. The two inverters have to be configured differently to run in parallel rather than stand alone, so that means connecting a laptop and loading different configs everytime you join or separate the inverters. The biggest issue would be that parallel inverters have to share the same battery so you would also have to join the dc side.

What would be much simpler and achieve the same thing is to just run them in series, so you feed 120V out of the RV system into the ACin on the cabin system and have power assist enabled, so effectively the cabin inverter sees the RV as "mains" and can add it's output to the RV power.

No reconfiguration or joining of the batteries. Also they could run at different dc voltages, so the RV system could be 12V and the cabin 48V if required.

2

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Aric commented · Mar 03 at 06:49 PM

The series sounds like the simpler plan. I wonder would it be possible to connect the rv 120vac to the line in on the cabin, and also connect the 120vac cabin output to the line in on the rv Inverter charger? This way if the cabin was running larger loads it could take from the rv, but if the rv was running a larger load it could take from the cabin

0 ·

delf67 Aric commented · Mar 03 at 07:24 PM

You could do either/ or by re-plugging (or possibly some arrangement of interlocked contactors), but not both at the same time. I assumed that the RV would be capable of supplying any loads it had, and the bigger loads would just be in the cabin.

0 ·

Answer 4 · 2024-03-03T18:00:33Z

kevgermany answered · Mar 03 at 06:00 PM

Make sure that the transfer relay on the cabin system can support the load.

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

question