When using a EG4 6000XP with grid assist, would that be considered grid tied and i have to deal with all the utility provider interconnect nonsense?

[Darkwing]

Good morning everyone.

I am planning my solar system but i dont want anyone beisdes maybe building codes to talk into it.
So i dont want any interconnection issues with the utility and i want to grow my system slow on paycheck2paycheck basis.
So does anyone has experience if i would have to notify my utility about using that inverter or is this def non interconnect due to no export?
Thx alot and i hope i am not to crazy with this

 

[Adam De Lay]

The 6000XP is a "grid-connected" inverter. Power only flows from the grid to the inverter, not the other way around. It's classified as an "off-grid" inverter and you don't have to mess with the power co.

 

[Darkwing]

Awesome, thx for the quick answer. I was thinking same thing but i am pretty new to legal pv

 

[solar8484]

Technically, "off-grid" inverter/chargers that support grid assist are generating power in parallel with the grid. So, many POCO's do require an interconnection agreement or the inverter must be physically disconnected from the grid. Best to check with your POCO to be sure. Check the forum for posts about "off-grid" inverter/charger users getting busted by POCO's for even inadvertent small (<10W) grid backfeed when using grid assist. It's rare but it happens.

 

[Ampster]

Best to check with your POCO to be sure.

My guess is the OP will get an ambiguous answer from the POCO. Get a building permit and verify that your inverter cannot backfeed and move on.

 

[Darkwing]

Haha "wants an ambitious answer". U made my day.
Asking a POCO stuff like that is like asking a butcher if u r allowed to become vegan. They prob always have to say anything against it.
But is will check with them.

 

[ksmithaz1]

Someone correct me if I am wrong. I believe it's just an inverter with a built-in transfer switch. The "assist" is it pops the DPDT relay and sends the load over to the grid lugs instead of the inverter output.

 

[solar8484]

What you described is simple bypass not grid assist/support.

 

[ksmithaz1]

But I'd put a separate 150-200A ATS with the inverter as primary in front of the panel. Easier to visibly see how it's wired and working to any inspector, no need to break out any manuals to explain. Something like this:

https://www.amazon.com/dp/B07SSB956Z

 

[ksmithaz1]

What you described is simple bypass not grid assist/support.

Correct. The 6000XP does not have any "assist" function and does not "tie" directly to the grid AFAIK. It's an inverter with a built-in transfer switch. This makes for a very simple interconnect to a smallish "critical loads" or "solar output" panel with grid backup. OTOH I'd probably just go with a separate ATS if I had any plans to scale and/or I needed more than 25A, because it would simplify the overall design, and make it easier to visually see that you are not actually tied to the grid.

 

[Darkwing]

Well, i am planning to run my house on it.
And the reviews i saw so far show a pretty beefy device. And i monitor my load for good a year now with emporia and i never even get close to 6kw usage. And for the surges, i am stsy8ng in the 50 amps it seems to provide.
Lets see how i am able to actually get in tocuh with my poco since now-a-days you usually onlt get dave from antlanta Georgia on the phone

 

[ksmithaz1]

6KW = 240v@25A This is a split-phase 240v inverter. 25A not 50. Technically you could pull 50A at 120v assuming you could perfectly evenly distribute the loads on each phase, but you cannot pull more than about 30A on any one leg, not even that for any length of time. Internally you have 2x120v inverters in parallel, you cannot tie L1 to L2 Might be useful for you to give some details. One would assume you are wiring this to a (sub-)panel of some description, and your sustained load should not exceed 80% for more than 3 hours or so, thus no more than 20A/4800W 24x7.

I would be surprised if you can handle demand loads in a 1500sqft modern house with air conditioning with a single 6000XP. If you have all gas appliances or something, or a small cabin in the woods with a small mini-split. Had the 6000XP been available I would have 4 of them instead of two 18Kpv's (12KW of AC, 240v@50A) hooked to my 100A panel.

I generally never get close to 6KW on average. A tough day in the summer is ~120KWH or 5KW on average. The problem is DEMAND. What is your highest potential 5 minute DEMAND? My 4Ton can pull right at 5KW by itself in July around 1500 in the afternoon.

 

[Ampster]

.
So i dont want any interconnection issues with the utility

In California an inverter configured for backup and which is separated from the grid by a "break before make" manual transfer switch does not need an interconnection agreement. Look on your utilities website for a similar arrangement. Attached is the PG&E document, which you can see refers to all sorts of backup systems:

 

[Darkwing]

6KW = 240v@25A This is a split-phase 240v inverter. 25A not 50. Technically you could pull 50A at 120v assuming you could perfectly evenly distribute the loads on each phase, but you cannot pull more than about 30A on any one leg, not even that for any length of time. Internally you have 2x120v inverters in parallel, you cannot tie L1 to L2 Might be useful for you to give some details. One would assume you are wiring this to a (sub-)panel of some description, and your sustained load should not exceed 80% for more than 3 hours or so, thus no more than 20A/4800W 24x7.

I would be surprised if you can handle demand loads in a 1500sqft modern house with air conditioning with a single 6000XP. If you have all gas appliances or something, or a small cabin in the woods with a small mini-split. Had the 6000XP been available I would have 4 of them instead of two 18Kpv's (12KW of AC, 240v@50A) hooked to my 100A panel.

I generally never get close to 6KW on average. A tough day in the summer is ~120KWH or 5KW on average. The problem is DEMAND. What is your highest potential 5 minute DEMAND? My 4Ton can pull right at 5KW by itself in July around 1500 in the afternoon.

I should tell that I'm German and my electric bill was never higher than 150 bucks with an average of 7,500 kilowatt hours a year

 

[PotusGobbleBottom]

emporia

Emporia is terrible at showing peaks of any circuit. You literally need to be watching the seconds view to know anything. If the data is 5 minutes old it seems to be averaged and not accurate for peaks.

 

[ksmithaz1]

I should tell that I'm German and my electric bill was never higher than 150 bucks with an average of 7,500 kilowatt hours a year

None the less, the problem is always DEMAND, and the 6000XP is not 50A, it's 25A@240V. You need to track peak demand to determine your needs.

 

[Darkwing]

Will def do more homework after your comments here...but the inverter idea is the right direction, zero export but grid as backup.

 

[Ampster]

Emporia is terrible at showing peaks of any circuit.

Why does that matter to you? It is all about kwhs for me. In that regard, the Emporia does a good for me. I also use it to charge my EVs from excess solar. It can change the current in the EV charger so I neither consume or export much when the EV is charging.

 

[ksmithaz1]

You keep saying zero "export" which implies it ties to the grid. The 18Kpv can tie to the grid and set "zero-export". The 6000XP is incapable of grid-export, it allows grid backup for the solar/inverter. A subtle difference. If you truly don't need more than 25A of peak demand on any one leg I think the 6000XP is almost a no-brainer. What is your current panel? current service? I would guess 75-100A based on your comments.

 

[ksmithaz1]

Why does that matter to you? It is all about kwhs for me. In that regard, the Emporia does a good for me. I also use it to charge my EVs from excess solar. It can change the current in the EV charger so I neither consume or export much when the EV is charging.

Because the OP wants to use a 240v/25A non-grid tied inverter. Then he mentioned 50A would be good, and Emporia as a reference for his demand needs. I don't know a thing about the product, but if you expect to run your house from an inverter, it needs to be sized for your demand not your average usage. He may well only need about 20A continuous on any leg. OTOH a mini-split and a toaster oven while brewing a pot of coffee, and the fridge kicking on may have an impact on that demand. On that front, he may still be ok if he makes sure to split the higher demand items so that they are on opposing legs.

The problem is it's really easy to hit > 25A for a few minutes, where your average might be 2 or 3. This is the electric utilities problem as well, your systems must be scaled to meet demand. Now if you don't mind an occasional overload/switchover that's perfectly valid as well, but in the case of the 6000XP it will shut off, for a bit, then shut back on after the overload clears and likely some timer expires, probably 5 min or something. Perfectly reasonable way to run it, but you don't want to have hours worth of 5 minute grid intervals either thus modestly accurate demand measurements would be helpful to avoid disappointments.

With the low demand we seem to intimate sounds like a fun project, with a rather modest ROI.