First EG4 Hybrid Inverter/Solar/Battery Setup Help

Ok, I am fine with doing my own wiring, installation, etc. I do my own electrical, wiring, panels, meter boxes, etc. and I own a commercial IT company 18+ years.

I have done multiple very small setups I designed and use for solar powered on pole security camera setups, remote/camping setups but nothing to run an entire house or building.

Been doing some research and reading on the forums and would like to do my first larger setup to run my detached building/shop/office.

The detached building in question has a new 100AMP sub panel that is connected to the main panel in the house.

I have the following running off this 100AMP subpanel

18,000BTU 1.5-Ton 22 SEER Mini-Split AC and Heat Pump
24U Server Rack with NVR, 5 24 and 48port POE Switches
Enterprise Routers, VOIP Server
7 Monitors
High Performance 14900k/RTX4080 workstation
4 Intel Computers
Access Control
Garage Door/Opener
Medium Size Air Compressor
Security Cameras POE
ALL LED Lighting
Small Pool Pump running 18000 gallon above ground pool

I will get my clamp meter out and see what my max amperage draw is on the 100A panel when everything mentioned above is running

I would like to install an EG4 Hybrid inverter to connect to the 100amp grid power, connect 20KW battery bank, connect solar installed on the buildings roof and have generator connection (already have a 30amp generator outlet on outside of building for my 12,000 gas generator)...

Not sure if I should use a EG4 12KW, EG4 18KW.

I am a dealer of Dakota Lithium and I get amazing dealer pricing on their products. They have a 20KWH stackable 48V solar battery setup that I get an unreal price on. So the want/goal is to use that as my battery bank to connect to the EG4.

Dakota 5KWH-20KWH
11 Year Warranty
LiFePO4
51.2V
(I know I wont be using the inverter that it comes with). I can save about $250 getting the 20KWH battery stack without the inverter...



So, I would install the EG4 12 or 18KW, connect the 100amp grid feed from house into the EG4, connect my 100amp load center panel to the EG4, connect the solar array on the roof to the EG4, connect the 30AMP gas generator outlet feed and then connect the Dakota battery stack to the EG4.


Purpose of this thread is to understand some of the numbers on the EG4 hybrid inverters from EG4 themselves, or some of you that are very well experienced with these inverters..

For example, the EG4 18KW says 18000watts Max utilized solar power. So thats the max number of wattage you can connect to the MPPT inputs on the EG4, correct? So say I used 410w panels. I could connect up to 43 panels roughly to this EG4 18KW? Am I understanding that correctly? (Yes, I see there are 3 MPPT inputs an each has a max AMP rating so the panels would have to be split up between the 3 MPPT inputs right?)

Battery input. I need some clarification on that. Does the EG4 18KW refer to the 18000watt max PV input? So, can I connect my 20KWH Dakota battery stack to this EG4 18KW no problem? Is there a limit on how many KWH of battery capacity I can connect to it?

I also dont understand the AC Grib Power output numbers when reading the spec sheet. which states 240V@12000watts. So, can I only power a maximum of 12000watts connected to my 100amp load center panel?

Any clarification on some of these questions or recommendations or comments on what Im desinging/looking to setup would be appreciated.

Thank you in advance.


End results goal is to run this detached building/office off solar and battery and have grid power kick in when needed and have battery backup for the building in the event of a power outage....

For the 18,000W capacity, it would need to be divided among the three MPPTs. I would recommend sizing it within the voltage range of 141-600V for the arrays and utilizing a temperature coefficient calculator to compensate for the record low temperatures in your area.


The 18,000W would be the max solar power utilized. However, the 18kPV can handle a maximum solar input of up to 21,000W. The battery bank size does not have a recommended max per 18kPV, but you will be limited to a max charge/discharge current of 250A per 18kPV. The main thing I would check on the Dakota battery is what BMS protocols it offers.

These are the following protocols that have been tested: https://eg4electronics.com/wp-content/uploads/2024/04/EG4-18KPV-12LV-Battery-Compatibility-List.pdf

The AC Grid output power from the spec sheet would be rated for @240 12,000W with a max output current of 50A when the grid is assisting through the inverter power. When bypassing the grid, this can go up to 200A. However, battery and PV power will not be utilized during this time.

The figures vary slightly with the 12kPV; the maximum output current is 33.3A at 240VAC with an 80A bypass. Additionally, there is a maximum charge/discharge current of 167A at 48 VDC for each inverter.

Without knowing the average continuous load and size of the pool pump/air compressor, it would be hard to say which one I would recommend for this application.

It also might be worth looking into the 6000XP in parallel if you do not want or need the 200A bypass and grid sell back features.

EG4TechSolutionsTeam said:

For the 18,000W capacity, it would need to be divided among the three MPPTs. I would recommend sizing it within the voltage range of 141-600V for the arrays and utilizing a temperature coefficient calculator to compensate for the record low temperatures in your area.

Solar Panel Maximum Voltage Calculator - Footprint Hero

Calculate the maximum open circuit voltage of your solar array. Find your max solar panel voltage to correctly size your solar charge controller.

footprinthero.com

The 18,000W would be the max solar power utilized. However, the 18kPV can handle a maximum solar input of up to 21,000W. The battery bank size does not have a recommended max per 18kPV, but you will be limited to a max charge/discharge current of 250A per 18kPV. The main thing I would check on the Dakota battery is what BMS protocols it offers.

These are the following protocols that have been tested: https://eg4electronics.com/wp-content/uploads/2024/04/EG4-18KPV-12LV-Battery-Compatibility-List.pdf

The AC Grid output power from the spec sheet would be rated for @240 12,000W with a max output current of 50A when the grid is assisting through the inverter power. When bypassing the grid, this can go up to 200A. However, battery and PV power will not be utilized during this time.

The figures vary slightly with the 12kPV; the maximum output current is 33.3A at 240VAC with an 80A bypass. Additionally, there is a maximum charge/discharge current of 167A at 48 VDC for each inverter.

Without knowing the average continuous load and size of the pool pump/air compressor, it would be hard to say which one I would recommend for this application.

It also might be worth looking into the 6000XP in parallel if you do not want or need the 200A bypass and grid sell back features.

Click to expand...

Really appreciate the reply!

So the Dakota batteries have built in BMS and use RS232/RS485 for communication the data sheet says...


Thanks for the solar input I fo. I'll use the calculator to compensate for the low temps.

10/4 on the battery. So really just need to see if BMS can communicate with the EG4.... If it says RS232/RS485 that we are good based odd the link? Or do I need to check more info for BMS communication?


I am still not 100% clear on AC output. . So if I have say Solar, Batteries AND grid all supplying power to my load... then max output of all of those power sources combined output of inverter is 50Amp (240v@12000w)???


If I don't use any grid power then the inverter can output 200Amps (source being solar and batteries)???


This specific setup for my office/shop/pool motor I probably don't need the 18kPV like you mention. I could probably also leave the pool pump motor and air compressor on the main 100a panel and run off grid power and just run the office, lights, mini split, server rack off the inverter/solar/battery to start.

I'll get a full load here shortly then will have a better idea of what inverter and how much power is needed

Unfortunately, I was not able to find protocol details in the manual, so I cannot verify compatibility in a closed-loop configuration. Should they be incompatible, you have the option to operate the batteries in an open loop without BMS communication.

The maximum current output for the 18kPV is 50A. To facilitate the 200A bypass, the grid would pass through the grid input, bypassing the inverter's power. This scenario should only arise if the loads surpass the surge rating or the continuous load capacity of 12,000W.

EG4TechSolutionsTeam said:

Unfortunately, I was not able to find protocol details in the manual, so I cannot verify compatibility in a closed-loop configuration. Should they be incompatible, you have the option to operate the batteries in an open loop without BMS communication.

The maximum current output for the 18kPV is 50A. To facilitate the 200A bypass, the grid would pass through the grid input, bypassing the inverter's power. This scenario should only arise if the loads surpass the surge rating or the continuous load capacity of 12,000W.

Click to expand...

I sent an email to my Dakota sales rep to confirm BMS protocol info so we will see what they say.

I just put my clamp meter on the 2 120V grid feeds in my 100Amp shop subpanel from my house main panel. I turned on all LED lights in the office, shop inside and out, pool pump running, mini split AC running full blast cranked down to 64 degrees blasting cold air, server rack running, 7 monitors, high performance workstation PC, 3 other PCs, access control, VOIP, etc and i got the following:

Left Leg - 8.5 Amp MAX
Right Leg - 11 Amp max

I then turned on the air compressor which to be clear I use maybe 2-3x a year now that everything is battery powered Milwaukee and my Left Leg jumped from 8 amps to 20 Amps.....

Everything mentioned above in the 100 Amp panel is on 120V breakers except the Mini-Split which is 240V on a 30Amp double pole breaker.

So, after seeing how little power Im drawing, I think the EG4 6000XP is more than enough for what I want to do at this point??

Now it just comes down to how much solar and what panels.. Backside of my shop faces east and gets the morning sun. Front side of my shop faces west and gets the most intense sun till it sets.

I was thinking something like Qty 6 - Hyperion 395W Bifacial Solar Panels on the front side that gets the most sun and Qty 4 - Hyperion 395W Bifacial Solar Panel on the backside that gets the morning sun.

That would give me 3950watts and using the Solar Panel Maximum Voltage Calculator that comes to 429V which is under the EG4 6000XP DC480V Max....


Thoughts? I know nothing about these panels.. Will these work great? Or is there some other panel I should be looking at?

Here is the Dakota BMS communication information for the linked batteries above. Not sure if this helps you answer if they can connect and properly communicate with the EG4 Hybrid inverter...

I've heard positive feedback about those panels. Did you account for the temperature coefficient and record lows in your area? Based on your load requirements, a 6000XP would be suitable. However, if you plan to use the full 100A, I recommend using two in parallel. This setup would handle any surges in the shop, ensure full 100A grid bypass, and provide redundancy in case of a failure.

Unfortunately, I still cannot confirm if these battery modules will communicate. The information in the manual does not clarify whether the RS485 port is for proprietary communication between the battery module and the inverter module via Dakota. The section about the LCD display does not reference a protocol list. I recommend sending them an email to inquire if the battery module will communicate with third-party inverters.

Thanks for the information I'm good on a single 6000 XP. I put the 100 amp service in not knowing what the draw would be and wanted capacity when I built my office and Shop but what I have installed now is the max that will ever be installed as I'm moving in the next year or so and I'll be taking the 6,000 XP with me. At that point maybe I'll add a second one for the new shop.

I have an email in the support at Dakota asking your exact question so we'll see what they come back and say about third party inverter communication with their batteries

Also, I did account for temperature coefficient and record lows my area.

Gameplanning how Im going to install this EG4 6000XP in my shop and connect it to my existing 100amp subpanel that is grid fed from my house main panel.

Having the ability to bypass the EG4 at any time and restore 100% grid power feed to my 100amp panel is very important since it runs my entire office and shop, servers, etc. If the EG4 goes down for whatever reason, I need to very quickly be able to switch the panel being fed from my grid as it does today.

So, my gameplan after doing some research and watching some videos is to install bagged tap connectors on the 2AWG copper THHN feed legs coming from the house main panel into my 100amp sub. I would then mount the EG4 6000XP right next to my existing 100amp shop panel, and run new 4AWG THHN from the bagged tap connectors on the 2 grid legs, through conduit and into the Grid L1 and L2 input on the EG4.

Next I would install a 60AMP double pole breaker in the first spot right below the 100AMP main shutoff breaker in my 100amp existing panel and run 6AWG THHN (Red, Black White and Green) through conduit and into the Ground and Neutral bars in the EG4 and the L1 and L2 load outputs on the EG4. The existing 100amp panel is unbonded since its a subpanel and has separate grounding rod in the ground outside connected to the panels ground bar because its a detached building.

I would then install the blocking device that doesnt allow the EG4 load feed 60Amp breaker and 100Amp main breaker to be on at the same time. That way, anything ever happens to the EG4, I can turn the EG4 load backfeed into the 100amp panel off and turn the 100amp main on to restore grid only power to the panel.

This is a picture of my existing 100amp shop panel. The left and right 2AWG Green THHN marked with red tape on left and right in bottom of panel are the 2 feed wires coming from the house main panel. This is where I will put the bagged tap connectors to tap into to feed the grid L1 and L2 inputs on the EG4.

I will then add my batteries to the EG4 and connect solar on shop roof to PV inputs on EG4.

Thoughts on this? See any potential issues or is my plan sound good to go to do what I want.