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EG4 6000XP Grid Feed

Ace201

New Member
Joined
May 2, 2024
Messages
4
Location
Calgary Alberta Canada
I’m looking to add a EG4 6000XP to my home. I’m currently selling all my solar power to the grid then buying back what I need. Transmission fees are killing me. So I thought adding the 6000XP would make sense. My goal is to feed the house and only send the surplus into the public power grid. I’m finding people saying yes they use it this way and yet some other ls say you can’t use the 6000XP that way. Some definitive answers would be appreciated…
 
What part of "off grid" is not clear? Note: You may be able to put it between your existing solar and the main panel for additional solar. The existing solar will export to the grid. But, the 6000xp will NOT export to the grid.

1715023266878.png
 
What part of "off grid" is not clear? Note: You may be able to put it between your existing solar and the main panel for additional solar. The existing solar will export to the grid. But, the 6000xp will NOT export to the grid.

View attachment 213661
It’s been suggested that using the 6000XP is exclusively for off grid. I want to be able too run on batteries part time, while the batteries are full I want to send the surplus power from my solar array to the grid. Currently I have a two way meter and I sell everything my PV system creates to the city grid. I then buy back the power from the grid to run the house.
 
It’s been suggested that using the 6000XP is exclusively for off grid. I want to be able too run on batteries part time, while the batteries are full I want to send the surplus power from my solar array to the grid. Currently I have a two way meter and I sell everything my PV system creates to the city grid. I then buy back the power from the grid to run the house.

There has been no suggestion -- it's just a hard fact. 6000XP can't back-feed the grid.

No one knows the details of your setup, no doubt what you want to accomplish is possible, but the 6000XP isn't going to be part of feeding anything back to the grid.
 
There has been no suggestion -- it's just a hard fact. 6000XP can't back-feed the grid.

No one knows the details of your setup, no doubt what you want to accomplish is possible, but the 6000XP isn't going to be part of feeding anything back to the grid.
The 6000XP cannot invert battery energy to AC power when in Bypsss Mode (hence the reason it is a off-grid inverter), but is there anything in the manual or specifications stating that it will prevent excess energy from grid-tied inverters connected to the EPS Output (Critical Loads Panel) from passing-through the Bypass Relay when the inverter is closed (inverter in Bypass Mode)?

I’m not recommending this nor saying it will function in this way, just clarifying that Off-Grid inverters are ‘allowed’ to pass-through excess AC power from grid-tied PV inverters to their AC output (while not being able to pass out any AC power the inverter itself generated from battery energy) and also pointing out that the manual is silent on this entire topic.

The Conext SW is an example of an off-grid inverter that allows excess power from grid-tied inverters on it’s AC output to export out if it’s AC input: https://www.se.com/us/en/download/document/SW-NA_OG_975-0638-01-03/

Look at the section on ‘AC Couple Smart Charge’ on page 1-14:

‘As long as the battery is able to accept the energy, the Conext SW will continue diverting excess PV production to the battery. Once the battery bank is at a level such that not all excess energy from the PV Inverter is being absorbed, the balance will then flow out to upstream loads in the house that are not connected to the Conext SW’s AC output port.

Of course, the Conext SW was one of the first Off-Grid inverters to support AC Coupling and the manual is full of sections describing how to use AC-Coupling, so I’m not saying the 6000XP will function at all like the Conext SW when AC-coupled PV is connected to the AC Output (EPS Output).

I’m just pointing out that Off-grid Inverters are ‘allowed’ to pass-through excess AC power coming from grid-tied PV connected to the AC Output (as proven by the Conext SW).
 
Can't you add a subpanel to the output side of the 6000xp move some loads over to that charge batteries and bypass until battery is full then switch to inverter shut off the bypass until battery reaches 20% and do it all over again next day. It's not best way to do things having your load flip daily I suppose an AC unit, stove, water heater those things don't care being flipped daily. I'm planning this for my 4 ton AC unit I just want to charge during off peak then use the inverter for 4 hours a day during peak take highest demand off the grid. I don't have enough battery yet to go 4 hours at 4000 watts but maybe 3 hours depending how many times it cycles. I don't have any solar setup yet working on that after I get the inverter and battery setup.

The fact that he has a grid tied solar on the main panel 6000xp wouldn't know where the power is coming from just getting current from the panel.
 
I’m looking to add a EG4 6000XP to my home. I’m currently selling all my solar power to the grid then buying back what I need. Transmission fees are killing me. So I thought adding the 6000XP would make sense. My goal is to feed the house and only send the surplus into the public power grid. I’m finding people saying yes they use it this way and yet some other ls say you can’t use the 6000XP that way. Some definitive answers would be appreciated…
If you're selling power to the grid, you must have a grid tied inverter.
If you put the 6000XP behind your grid tied inverter power from the grid tied inverter will feed the grid input of the EG4 and excess will go to the grid.
 
It’s been suggested that using the 6000XP is exclusively for off grid. I want to be able too run on batteries part time, while the batteries are full I want to send the surplus power from my solar array to the grid. Currently I have a two way meter and I sell everything my PV system creates to the city grid. I then buy back the power from the grid to run the house.
you have probably figured this out by now... you simply cannot backfeed to the grid with 6000xp. What you will need to do is use a 'hybrid' inverter like the eg4-12kpv, eg4-18kpv, Sol-arc, Fortress, Conext, etc. Connect a 60a circuit from your main panel to "Grid in/out", and move your existing PV interconnection to the hybrid "Generator" input. Them you could have a dedicated "critical loads" subpanel connected to "Load", or not.

This would charge batteries, and backfeed after they are full, and you *could* program limited backfeed over night to run house loads and draw down batteries, delaying draw from Grid until you hit your battery LV setpoint.
 
If you're selling power to the grid, you must have a grid tied inverter.
If you put the 6000XP behind your grid tied inverter power from the grid tied inverter will feed the grid input of the EG4 and excess will go to the grid.

This is exactly what I am doing, with a 8 year-old SolarCity/Tesla grid-tied system (5kW PV and two PowerWalls), to which I recently added a 6000XP, 6.4kW of PV and two WallMount batteries. The Telsa system used to power the whole house (about 70% of the time). I cut into a sub-panel feed from the main, and patched it through a transfer switch, and now the 6000XP serves the sub. I can still go back, if necessary. It effectively has removed half the load from the old Tesla system, with no mods to the Tesla system, nor a new connection to the actual grid/utility feed. It's invisible to the utility and Tesla system. It should be noted that I specifically put about half the house on a sub-panel eight years ago (during a massive remodel), with just such a future application in mind. I moved a few circuits around to get a better bulk load balance between the Main and Sub, as well as between legs L1 and L2.

You can do the same thing with a new critical loads panel that has had various loads shifted over to it.
 
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I’m looking to add a EG4 6000XP to my home. I’m currently selling all my solar power to the grid then buying back what I need. Transmission fees are killing me. So I thought adding the 6000XP would make sense. My goal is to feed the house and only send the surplus into the public power grid. I’m finding people saying yes they use it this way and yet some other ls say you can’t use the 6000XP that way. Some definitive answers would be appreciated…
Can we get more information on your setup?
I have not personally attempted this, however as faford mentioned, the EG4 6000xp does support AC coupling with an existing grid tied solar inverter. This is done by repurposing the Generator connection. Before I go too deep, a purpose built hybrid inverter would be easier to troubleshoot as AC coupling will likely have some unique challenges. One particular trade off is that you may need to enable the AC first setting, and configure it to force bypass mode during normal daylight hours. This should allow your current grid tie inverter to charge the battery, pass excess power to the main panel, and back feed the grid. The trade off is that 6000xp would essentially be following a predetermined schedule which will introduce a certain amount of inefficacy.

I would like to offer an alternative as well.
First, check your current grid tie inverter and determine if you have more than one string of solar panels connected to it.
If you do, the easiest and most cost effective solution in this situation is likely removing one of the strings from the grid tie inverter and connecting it to the 6000xp instead. The idea is some of your panels would feed the grid tie inverter, and some would feed the 6000xp. It's not a perfect solution, but it does allow you to benefit from a battery without dropping the cash for a hybrid inverter.

2024-10-19 23_56_40-EG4-6000XP-Manual.pdf.png 2024-10-19 23_59_54-EG4-6000XP-Manual.pdf.png
 

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