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Revised Diagram for Comment: 24v RV build; 240v AC mini-split

David S

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I revised a previous schematic based on comments, so here's the new view. COMMENTS PLEASE...

Details:
24v 3p8s Eve/Lishen battery bank
Electrodacus SBMS0 BMS
DSSR20's x 4
2x 24/3000 Victron Multiplus
1x Victron Orion 24/12 70a
Shore Power
8x 300w Solar in 2p config for the DSSR20's
3kW Dual fuel generator
240v Mini Split AC
24V compressor fridge

Goal: Create an electrical system that will allow me to stay 14 days straight at a CA state beach OR a CA desert dispersed camping site (think Alabama Hills) with no hookups. Water and dump stations are generally available, but there are no electrical hookups. I want full electrical living, including AC overnight, but I will avoid the very hottest months in the very hottest locations. Generally, I will get very good sun, given the location. Genset is strictly for backup, in the event of crappy sun.

I'm removing the 6kW Onan Diesel genset from my 37' Super C RV and replacing it with a fully inverted system. I'm removing the roof mounted A/C's and replacing them with the mini split. I'm updating the existing propane/120v ac evap fridge with a 24v compressor unit and I'm removing the propane heater in favor of a diesel heater + heat pumps in the mini-split. Mini-split is a 240v ac unit, 30kW dual zone and I'll be replacing the existing AC units with new Maxxair fans. Phase 2 might include diversion heating via the DSSR's for hot water. Primary control will be via SBMS0, with a Home Assistant installation + Mosquitto MQTT to intake info and display a dashboard. Also currently working on a Mikrotik cellular booster for LTE & 5G. So much fun...
 

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I revised a previous schematic based on comments, so here's the new view. COMMENTS PLEASE...

Details:
24v 3p8s Eve/Lishen battery bank
Electrodacus SBMS0 BMS
DSSR20's x 4
2x 24/3000 Victron Multiplus
1x Victron Orion 24/12 70a
Shore Power
8x 300w Solar in 2p config for the DSSR20's
3kW Dual fuel generator
240v Mini Split AC
24V compressor fridge

Goal: Create an electrical system that will allow me to stay 14 days straight at a CA state beach OR a CA desert dispersed camping site (think Alabama Hills) with no hookups. Water and dump stations are generally available, but there are no electrical hookups. I want full electrical living, including AC overnight, but I will avoid the very hottest months in the very hottest locations. Generally, I will get very good sun, given the location. Genset is strictly for backup, in the event of crappy sun.

I'm removing the 6kW Onan Diesel genset from my 37' Super C RV and replacing it with a fully inverted system. I'm removing the roof mounted A/C's and replacing them with the mini split. I'm updating the existing propane/120v ac evap fridge with a 24v compressor unit and I'm removing the propane heater in favor of a diesel heater + heat pumps in the mini-split. Mini-split is a 240v ac unit, 30kW dual zone and I'll be replacing the existing AC units with new Maxxair fans. Phase 2 might include diversion heating via the DSSR's for hot water. Primary control will be via SBMS0, with a Home Assistant installation + Mosquitto MQTT to intake info and display a dashboard. Also currently working on a Mikrotik cellular booster for LTE & 5G. So much fun...
I gotta stop posting at midnight PST. Everyone misses the posts and they sink to the bottom of the what's new queue.
 
I am building a similar system.

I will be using the SBMS0.
One of the things I like about the Electrodacus Is the expandability of the system.

To start with I will have 8 280 ah Cells, depending on how that works out could double it.

I will only have the one 3000 Inverter.

I will be installing it in an MCI Bus conversion, waiting on Batteries now.

I have a 120 volt 12k BTU Minisplit, I would like to be able to run it some of the time and refrigerator all of the time along with various other loads.

I like the design of your system, the 240 Minisplit could be an advantage, I considered one, It would be nice to have two inside units, one in the front and one in the back. There are no 120 volt outside units that support two inside units, would need at least 24k BTU.

Although I wired for 50 amp I kept everything at 120 volt due to a lot of the places we go have 30 amp 120 volt shore power.

We spend most of our time in Parks with hookups, with few times Boondocking, hoping to do more Boondocking with more capability (the wife does like her electricity).

I also have hot water diversion planned for the future, Undecided if I should get an existing Hot water heater and replace one of the elements with a 24 volt element or create a separate very well insulated tank for the diversion tank.

Peter

Solar design detail3.jpg
 
I am building a similar system.

I will be using the SBMS0.
One of the things I like about the Electrodacus Is the expandability of the system.

To start with I will have 8 280 ah Cells, depending on how that works out could double it.

I will only have the one 3000 Inverter.

I will be installing it in an MCI Bus conversion, waiting on Batteries now.

I have a 120 volt 12k BTU Minisplit, I would like to be able to run it some of the time and refrigerator all of the time along with various other loads.

I like the design of your system, the 240 Minisplit could be an advantage, I considered one, It would be nice to have two inside units, one in the front and one in the back. There are no 120 volt outside units that support two inside units, would need at least 24k BTU.

Although I wired for 50 amp I kept everything at 120 volt due to a lot of the places we go have 30 amp 120 volt shore power.

We spend most of our time in Parks with hookups, with few times Boondocking, hoping to do more Boondocking with more capability (the wife does like her electricity).

I also have hot water diversion planned for the future, Undecided if I should get an existing Hot water heater and replace one of the elements with a 24 volt element or create a separate very well insulated tank for the diversion tank.

Peter

View attachment 45844
Thanks for replying! These are exciting projects, that's for sure. WRT to 120v vs. 240v, you should check out @cinergi's build thread. He's built a similar system, with a requirement to drive a 240v mini split, and his testing (plus Victron's documentation) make it really clear that a dual inverter system easily handles 120v shore power. More specifically, if you are running the Multiplus's in split phase and if you connect a 30a > 50a dog bone adapter to the 50a shore power line, the Victron's will recognize that both legs have the same phase and accommodate. The leader inverter will take the single phase and use it to charge batteries and feed its leg. The follower inverter will continue to invert, providing power to the second leg. That said, I’m not sure if the aims inverters have the same capabilities.

WRT diversion, I'm playing with a 24v 600w heating element right now, using it as a capacity testing load dump. Dacian has suggested that a 36v 1200w element would be a better diversion target. Biggest challenge I see at this point WRT diversion is that you have to control both the diversion load (which the DSSR/SBMS0 handle) and the thermostat for the water heater. Haven't figured that out yet, but it's a later todo item as I figure out if I will actually have excess solar capacity or not.
 
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Thanks for the tip to look at cinergi’s build, he got some interesting stuff going on and an awesome build.

Those Multiplus inverter\ chargers have some awesome tech built into them, one of the best features is the ability for the SBMS0 to control it right out of the box, Another great feature is the ability to make up for low power from shore power from the batteries.

When\if the Aims fails, one of those will be on the top of the list to replace it.

The Aims inverter does not have all the same capabilities, but I already have the AIMS inverter\charger PICOGLF30W24V120VR, I will have to make a few modifications to the switches before the SBMS0 can control it.
 
I revised a previous schematic based on comments, so here's the new view. COMMENTS PLEASE...

Details:
24v 3p8s Eve/Lishen battery bank
Electrodacus SBMS0 BMS
DSSR20's x 4
2x 24/3000 Victron Multiplus
1x Victron Orion 24/12 70a
Shore Power
8x 300w Solar in 2p config for the DSSR20's
3kW Dual fuel generator
240v Mini Split AC
24V compressor fridge

Goal: Create an electrical system that will allow me to stay 14 days straight at a CA state beach OR a CA desert dispersed camping site (think Alabama Hills) with no hookups. Water and dump stations are generally available, but there are no electrical hookups. I want full electrical living, including AC overnight, but I will avoid the very hottest months in the very hottest locations. Generally, I will get very good sun, given the location. Genset is strictly for backup, in the event of crappy sun.

I'm removing the 6kW Onan Diesel genset from my 37' Super C RV and replacing it with a fully inverted system. I'm removing the roof mounted A/C's and replacing them with the mini split. I'm updating the existing propane/120v ac evap fridge with a 24v compressor unit and I'm removing the propane heater in favor of a diesel heater + heat pumps in the mini-split. Mini-split is a 240v ac unit, 30kW dual zone and I'll be replacing the existing AC units with new Maxxair fans. Phase 2 might include diversion heating via the DSSR's for hot water. Primary control will be via SBMS0, with a Home Assistant installation + Mosquitto MQTT to intake info and display a dashboard. Also currently working on a Mikrotik cellular booster for LTE & 5G. So much fun...
Updated Schematic
 

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Updated with additional feedback from Dacian Todea and others. Simplified and added new features. Feedback appreciated.
 

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Thanks for replying! These are exciting projects, that's for sure. WRT to 120v vs. 240v, you should check out @cinergi's build thread. He's built a similar system, with a requirement to drive a 240v mini split, and his testing (plus Victron's documentation) make it really clear that a dual inverter system easily handles 120v shore power. More specifically, if you are running the Multiplus's in split phase and if you connect a 30a > 50a dog bone adapter to the 50a shore power line, the Victron's will recognize that both legs have the same phase and accommodate. The leader inverter will take the single phase and use it to charge batteries and feed its leg. The follower inverter will continue to invert, providing power to the second leg. That said, I’m not sure if the aims inverters have the same capabilities.

WRT diversion, I'm playing with a 24v 600w heating element right now, using it as a capacity testing load dump. Dacian has suggested that a 36v 1200w element would be a better diversion target. Biggest challenge I see at this point WRT diversion is that you have to control both the diversion load (which the DSSR/SBMS0 handle) and the thermostat for the water heater. Haven't figured that out yet, but it's a later todo item as I figure out if I will actually have excess solar capacity or not.
The SBMS0 has two extra unused analog inputs, one could be used for the temp sensor of water tank. I was thinking they would be nice for controlling the solar tracking. Alas my panels are out of range for 24v system. I'm studying the schematics to see if it can be modified to make a 48v unit. Using the director for water heat stops you from what looks like a good idea of using the DSSR's in morning and evening, and redirecting to a MPPT for the noon power grab. Get best of both worlds generating power. Of course the purpose of the DSSR is to transfer the power when batteries are full so no need for more power for them I guess. But a 3 some so you can fill batteries faster and get to heating water sooner.....
 
additional minor updates based on feedback.
 

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his new DSSR60's are in final testing. Think you can put 4 panels on one of them.
And there should be enough ma to enable both victrons with one signal wire, and free up a signal so you can enable the 12v separate from 24v fridge if you wanted. Unless turning them on requires the master first.
Did you leave off your water heater? But it looks right to me at 3am.
 
Thanks for replying! These are exciting projects, that's for sure. WRT to 120v vs. 240v, you should check out @cinergi's build thread. He's built a similar system, with a requirement to drive a 240v mini split, and his testing (plus Victron's documentation) make it really clear that a dual inverter system easily handles 120v shore power. More specifically, if you are running the Multiplus's in split phase and if you connect a 30a > 50a dog bone adapter to the 50a shore power line, the Victron's will recognize that both legs have the same phase and accommodate. The leader inverter will take the single phase and use it to charge batteries and feed its leg. The follower inverter will continue to invert, providing power to the second leg. That said, I’m not sure if the aims inverters have the same capabilities.

WRT diversion, I'm playing with a 24v 600w heating element right now, using it as a capacity testing load dump. Dacian has suggested that a 36v 1200w element would be a better diversion target. Biggest challenge I see at this point WRT diversion is that you have to control both the diversion load (which the DSSR/SBMS0 handle) and the thermostat for the water heater. Haven't figured that out yet, but it's a later todo item as I figure out if I will actually have excess solar capacity or not.
Incredible system. I'm interested in your split mini for two reasons: 1, installing the cassette somewhere central is my preference in my 31' Shasta. I don't want it over my bed. I really want the kitchen the coolest. 2. I know 220v is the way to go with these, but I'm doing a much smaller system. Do you have a strong pitch for why I must have a 220v unit (my HVAC guy said the 110v units are just not very good; I put in 220 in my rental house.)
 
I am going 220 in my rig because a) my rig is already 50 amp split phase, so it fits naturally, b) I want a 2 zone system because the size and layout of my rig make it unlikely a single head unit will be sufficient, and c) I want the extra capacit that dual inverters give by splitting the 120 legs. Otherwise I’ve not heard a single complaint in my research about the performance of the 110 units in an RV.
 
I’ve not heard a single complaint in my research about the performance of the 110 units in an RV
Ditto. I have looked at this hard and no complaints with 110 in rv's.... I still may go 240 because of lack of room for two compressors
 
Are you sure you need a 24k ac, I use an 12k for a large bedroom and a 15k for a 750 sf room, both are overkill
 
Camping in the desert: it typically cools off at night in the desert unless you are there in the summer. Even so an evaporative cooler has a low power draw and only uses 3-5 gallons of water a day. A lot of campers only use the a/c during the afternoon or to cool down the camper in the evening and then shut it off. A professional solar designer/installer told me a genset that is only used occasionally (like for running an a/c for a few hours ) can dramatically lower the cost of your solar system,

If you design carefully you could put together a basic system that doesn’t run the a/c for dramatically less investment.

Side note Dometic has a 6,000 btu a/c until that runs on 12v and only draws about 300 watts.

What model is your Super C?
 
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