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48v Growatt 5000 240vac for a RV ? about connecting to RV panel considered split phase 120v?

motomarc

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I posted before about the system I am trying to decide on proper parts for it & need help with that end.
I am getting closer to making my purchase & want to make sure not to mess up.

the ? is the Growatt 5k unit is 240v ac output.
if it was hooked to a off grid home panel it would be the same as shore power in the breaker box correct? 2-120v legs ?
that said if I take 1 leg of 120v from Growatt to each leg of the 50amp 240 breaker in my RV that would be the same as shore power connection correct? cause that's how it is wired from factory 50amp.
granted I would only have 25amps on each leg through the Growatt 5k, not 50 amps per leg like shore power but more then enough for my use.

or will the Growatt unit not work like that? ONLY 240V pulling from both legs at all times?

this would save a lot of hassle & $$$ of buying 2 - 120v 3k units.
I am trying to make it as easy as possible to put on my 5th wheel just hooking into the existing panel not messing with the 12volt at all.
 
I posted before about the system I am trying to decide on proper parts for it & need help with that end.
I am getting closer to making my purchase & want to make sure not to mess up.

the ? is the Growatt 5k unit is 240v ac output.
if it was hooked to a off grid home panel it would be the same as shore power in the breaker box correct? 2-120v legs ?
A Growatt 5000w 240vac may be just that - 240vac ONLY. If so, it won't have 120v split-phase (US) legs - only 240v.

Could you post a link to the exact model? and then we can give better comments / explain how to hookup up 120v legs etc. :)
 
Watch some of David Poz's You Tube videos on his Growatt 5k units. It only puts out 240v and does not provide split phase 120v... If you want or need that you will need to add a center-tap transformer on the output (David Poz calls it an auto-transformer)...
 
Watch some of David Poz's You Tube videos on his Growatt 5k units. It only puts out 240v and does not provide split phase 120v... If you want or need that you will need to add a center-tap transformer on the output (David Poz calls it an auto-transformer)...
Yes on @DavidPoz - at 2:05 in this one he mentions the 120v/120v unit and he has others in more detail.
 
There are a few topologies that inverters implement to achieve their power outputs.

Topology 1:
Sol-Ark 12k style, where they natively provide split-phase on a single inverter, 240v across L1 and L2, and 120v across either line and the neutral. Stacking inverters, just parallels these line connections (with sync cable to sync their sine waves) and provides more current capability.

Topology 2:
MPP LV6548 style, where 240v requires minimum two inverters, each one providing 120v and neutral, to get 240v, you use the hot wire output on each respective inverter as a pair to make your L1 and L2 outputs. You can stack them up to 6 inverters (with sync cables,), with up to three 120v inverters on each leg (3 in sync on one leg, other 3 in sync on other leg, each pair having sine wave 180 degrees apart).

Topology 3:
Growatt 5k style, where the inverter only makes 230v (or can be set to 240v for USA use), typically might use this in countries where they do not require split-phase. David Poz happens to use workaround of adding in an external center-tap transformer on output for use in the US to support 240v/120v split-phase. Stacking these, parallels the output connections, using sync cable to sync their sine waves, adding current capacity to the system.

NOTE:
Let's not get into 3-phase and stacking, that is another topology altogether...
 
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I posted before about the system I am trying to decide on proper parts for it & need help with that end.
I am getting closer to making my purchase & want to make sure not to mess up.

or will the Growatt unit not work like that? ONLY 240V pulling from both legs at all times?

Do you have any 240V power using devices in your RV? Most people don't.

So essentially most RVs with 50A plug use that - 2x 120V and not 240v.

You can get one of the New Growatt 6000W

They provide native Splitphase output. Not cheap - but doing everything you need in one Box.
 
Do you have any 240V power using devices in your RV? Most people don't.

So essentially most RVs with 50A plug use that - 2x 120V and not 240v.

You can get one of the New Growatt 6000W

They provide native Splitphase output. Not cheap - but doing everything you need in one Box.
no 240v appliances just the 50amp shore power and 5500 onan connected to transfer switch giving me 120v x 2 legs for RV panel.
I know most people go 3k inverter in each side of rv power panel so all outlets are powered.
I was just trying to purchase a single unit that can give me 120v on each leg and the unit can supply power like that.
I can always move wires on breakers to get the power that I want on 1 side of the panel, that's simple enough basically going to have 1 High efficient AC, it's on a 15amp breaker now.
I haven't checked the amp draw and startup amp draw yet.
a microwave if needed, not running at same time LOL.. then TV ,12v lights , usb chargers. so my load won't be that high.
the plan is 48v 280ah or 320ah battery & as much solar as the unit can handle in DCV @ VOC.
figured 220v output in panels since max is 250v figured covering the cold days so not to over voltage the system.

any input on building this out is appreciated. panel suggestions etc.
thank you.
 
You need to do a power audit. Without that it's difficult to help you cost effective.

When you got a generator your can usually go lighter on the batteries - since your only need to account batteries for 1-2 days.
For the odd days of winter bad weather you can just fire up the generator and recharge.

Start with some sort of power meter and track what you need for 24hrs. 48h and one week.


This is my RV configuration, I really never use more then 3000W. Even the Microwave and the A/C run at the same time (at the limit but running)
all-in-one-rv-system-v3-png.74774
 
The easiest solution would be to come out of your inverter and into a mid-point transformer to give you balanced split phase yea?
 
The easiest solution would be to come out of your inverter and into a mid-point transformer to give you balanced split phase yea?
just buy a Inverter which already has that integrated:

 
A Victron Multiplus II 12/3000/2x120-50 would be the easiest solution. It is made to do exactly what you are looking for. Super simple to hook into a 50A RV system. Not cheap, though ($1600).

https://baymarinesupply.com/victron...-3000va-120-50-2x120vac-inverter-charger.html

I tried doing it with 2 separate inverters but it got complicated quick. Especially when you have to figure how to make it work with a 50A connection and a 30A connection. The MPII takes care of everything and makes it a no brainer.

DC wiring 290RL.jpg
 
You need to do a power audit. Without that it's difficult to help you cost effective.

When you got a generator your can usually go lighter on the batteries - since your only need to account batteries for 1-2 days.
For the odd days of winter bad weather you can just fire up the generator and recharge.

Start with some sort of power meter and track what you need for 24hrs. 48h and one week.


This is my RV configuration, I really never use more then 3000W. Even the Microwave and the A/C run at the same time (at the limit but running)
all-in-one-rv-system-v3-png.74774
the two chins battery's will only pull a 100 ah even if one is a 200 ah. . or this might be clearer. you can only use a 100ah out of the 200ah battery because you have them in series.. if i am right
 
the two chins battery's will only pull a 100 ah even if one is a 200 ah. . or this might be clearer. you can only use a 100ah out of the 200ah battery because you have them in series.. if i am right
you must have misread the diagram or I'm bad at drawing :p

the batteries are parallel. In parallel A and AH are added. While you are right in series - A and AH stay the same and voltage is added.

I can use 25.6V x 100AH + 25.6V x 200AH = 7680wh.
 
A Victron Multiplus II 12/3000/2x120-50 would be the easiest solution. It is made to do exactly what you are looking for. Super simple to hook into a 50A RV system. Not cheap, though ($1600).

https://baymarinesupply.com/victron...-3000va-120-50-2x120vac-inverter-charger.html

I tried doing it with 2 separate inverters but it got complicated quick. Especially when you have to figure how to make it work with a 50A connection and a 30A connection. The MPII takes care of everything and makes it a no brainer.

View attachment 75140
Multiplus II is tailor made for 240V 50amp RV service. The 48v version is a few $100 cheaper than the 12V/3000.

I'm planning on a 48V system also.
Full time in a big 5th wheel 4 years now.
I plan to keep the 12V system intact. Building more of a fixed home system than mobile.

The EG4 house batteries are too big to place in the 12V battery location anyway.

12V really on handles the lights and furnace fan in winter consistently. The rest of the 12V system is occasional use only. Awnings, slides, leveling jacks, electric brakes and break-away.

However, microwave, refrigerator, freezer a/c, water heater and outlets all require 120v.
I'll have a DC/DC converter charge the 12V batteries and increase storage capacity a small amount as well. Pulling the old OEM converter/charger from the system.

Multiplus II allows 50amp split phase pass through in a 48V/3000 configuration. Combining hybrid power sharing of shore, solar and battery input. I'm holding off on that inverter for now hoping they release a 5000W version that currently is only avaliable in a EU 230v version.
 
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