Complete guide for 48V using EG4 18k

[calc30]

AC or DC coupling?

DC: Are you unmounting the microinverters and selling them, along with converting all intervening wiring to be compatible with DC electrical code?

AC: feed into “generator ” port of 18kpv. In which case the AC output of the grid tie inverters cannot exceed the 12kw AC charging rating

Batteries: your simple choices are the 9540 approved EG4 batteries. Only two or three. You’re welcome for my collapsing of your design space

DC: Are you unmounting the microinvertrs and selling them? Answer: No

AC: Feed into "generator" port of 18kpv.

Answer/Questions:
I'm not sure what you all mean by feed into the generator port of the 18kpv. I mean, I understand the generator location, but what is feeding that, is it from the combiner 4 box, which then feeds directly into the generator? Stupid questions because I don't know any better, why can't I piggy-back (pig-tail off) of the PV from the combiner 4?

From what I gather, I leave the PV strings going into the combiner box 4, but move the power coming from the combiner directly to the generator port on the 18Kpv. if that is the case, what if I wanna use a gennie?

How would the 18kpv recognize/report the power going into the gen?

 

[calc30]

DC: Are you unmounting the microinvertrs and selling them? Answer: No

AC: Feed into "generator" port of 18kpv.

Answer/Questions:
I'm not sure what you all mean by feed into the generator port of the 18kpv. I mean, I understand the generator location, but what is feeding that, is it from the combiner 4 box, which then feeds directly into the generator? Stupid questions because I don't know any better, why can't I piggy-back (pig-tail off) of the PV from the combiner 4?

From what I gather, I leave the PV strings going into the combiner box 4, but move the power coming from the combiner directly to the generator port on the 18Kpv. if that is the case, what if I wanna use a gennie?

How would the 18kpv recognize/report the power going into the gen?

BTW - My Neutral Lug Kit LK225AHNHOM

 

[calc30]

Other than spending more money, is there an advantage of Sol-Ark15 vs 18Kpv vs Luxpower 12k? I don't want to be restricted because I was tried saving a few bucks.

I really like the Luxpower inventor, but I don't believe the amps reach 200.

 

[zanydroid]

AC: Feed into "generator" port of 18kpv.

Answer/Questions:
I'm not sure what you all mean by feed into the generator port of the 18kpv. I mean, I understand the generator location, but what is feeding that, is it from the combiner 4 box, which then feeds directly into the generator? Stupid questions because I don't know any better, why can't I piggy-back (pig-tail off) of the PV from the combiner 4?

You go Micros -> Combiner 4 -> Generator port

The "Generator" port really should be called a flexible port on these machines with different behavior depending on use case. For AC coupling, the relay on the port is used to drop the connection if frequency shift fails.

if that is the case, what if I wanna use a gennie?

You only have one "flexible" port so you're out of luck wrt out of the box support. AC transfer switch selecting between generator and AC string is one approach, another one is generator -> chargeverter -> DC bus of the battery

How would the 18kpv recognize/report the power going into the gen?

You'll have to ask an 18kpv owner that does AC coupling or EG4 support rep here. Should be able to get a precise answer.

 

[zanydroid]

I really like the Luxpower inventor, but I don't believe the amps reach 200.

LuxPower 12K should be the same as the 18kpv, just without EG4 branding.

18kpv is intended to be a SolArk 15K competitor.

 

[calc30]

You go Micros -> Combiner 4 -> Generator port

The "Generator" port really should be called a flexible port on these machines with different behavior depending on use case. For AC coupling, the relay on the port is used to drop the connection if frequency shift fails.


You only have one "flexible" port so you're out of luck wrt out of the box support. AC transfer switch selecting between generator and AC string is one approach, another one is generator -> chargeverter -> DC bus of the battery



You'll have to ask an 18kpv owner that does AC coupling or EG4 support rep here. Should be able to get a precise answer.

Thanks, that clears up almost everything

I'm assuming If the grid goes out, I'll still have power to the entire home, with solar and batteries, correct?

Does anyone one have suggestions on batteries? I'm an IT guy and love the look of rack mounted batteries, but I really love the sleek look probably better. Decisions... decisions...

 

[Quattrohead]

The EG4 Power pro indoor batteries are the best bang for the buck and combined with the 18K PV inverter will give you a system that can be officially inspected and approved if necessary.

 

[MaikaiLife]

Can someone tell me what size of Allen Key these are?

 

[solaruser120]

Looks like M8 hex wrench for the larger terminals and M5 for the smaller

 

[calc30]

Team -

I have paralysis from over analysis, so I haven't pulled the trigger just yet. However, I know I want to have whole home backup with net billing. During my final research of the of the main panel, I believe I found something troubling. It looks like I have lugs not wires coming from the meter to the main breaker panel. See the provided attachment to confirm. My apologies if I used the wrong terminology regarding lugs. Would someone confirm my findings?

 

[zanydroid]

Team -

I have paralysis from over analysis, so I haven't pulled the trigger just yet. However, I know I want to have whole home backup with net billing. During my final research of the of the main panel, I believe I found something troubling. It looks like I have lugs not wires coming from the meter to the main breaker panel. See the provided attachment to confirm. My apologies if I used the wrong terminology regarding lugs. Would someone confirm my findings?

Is this your panel, or someone else’s?

You do have wires here. Somebody posted a panel much like yours. Usually it’s busbar (flat metal) or wires from meter to main breaker. Lugs are basically terminals circuits start/end from, that are unfused. Busbar obligates use of ribbon CT, and even then they may not fit under. Gross

And yes this is an important thing to check, but there are ways to deal with it. It’s just a question of labor and laying out the equipment. You need to see if you can get CT (either regular or ribbon) under there. If not you have to add a second subpanel next to the main and move the house circuits there, or swap the main panel for one that is CT comparible . Both give you options to install the CTs

The additional advantage of the subpanel is that you can have all your circuits on backup. Well some people wouldn’t like that I guess

House circuits can be move to new panel one at a time as you have time

 

[calc30]

Yes, this is my panel. Attached is the entire panel.

I figured I would need at minimum a sub panel since I can't place the inverter between the meter and the main. I'm not adversed to moving all the circuits to the new panel. I really don't mind protecting all my loads. So, I can achieve same thing just moving all the circuits, correct?

I'm guessing I could leave the old CTs where they sit and then place the new inverter CTs at the top of the sub panel. I would need to move the PV breaker in the sub panel or wouldn't have solar during an outage, correct?

 

[zanydroid]

OK, so this is a surface mount panel, which makes it easier because you don’t have to flush mount another one or have a mismatch side.

What are the existing CT for?

Even if you can get the CT on there, you cannot provide emergency power to circuits on the main panel. You have to move EPS circuits to a subpanel after the inverter’s output. On an outage the inverter will isolate the input with its transfer relay and stop pushing AC through that side.

So the reason to leave circuits on the main typically is so that they automatically get excluded on a power outage, which can avoid running down the battery. There is not a perfect answer for how to pick circuits for one or the other, eventually we probably all go to smart load shedding.

You can feed the 18kpv through 200A plug on lugs, you should not need to use a breaker (and 200A branch breakers are anyway hard to find or non existent for a lot of panels). Plug on lugs are basically like breakers in that they plug into the bus, but they don’t have any overcurrent protection. I would guess the right plug on lug will take 4 spaces instead of 2 (because of the amount of current that can go through).

 

[calc30]

Those CTs are to monitor what is being pushed back to the grid.

Your comment "You can feed the 18kpv or sol15 through 200A plug on lugs", if I'm understanding you correctly, there are plugs you can purchase to connect to the main panel, and, if so, I'll just connect the 18k or 15k directly to that? Then the load from the 18kpv will go to the sub panel, correct?

 

[zanydroid]

Those CTs are to monitor what is being pushed back to the grid.

Are the CTs connected to the 18kpv or a different inverter? It sounded like you haven't bought it yet.

Yes you have the right picture in mind.

These are what the plugs look like. The picture might be not be for the 200A version

Siemens Sub Feed Lugs for 150A-225A Load Centers ECLK2225 - The Home Depot

Reliable product from the technology leader. Technology enabling reliability. When it comes to ready availability, easy installation, and fewer callbacks, you need a manufacturer you can trust. Our products

www.homedepot.com

 

[zanydroid]

Here is the HOM version

https://download.schneider-electric.com/files?p_enDocType=Instruction+sheet&p_File_Name=48840-229-01.pdf&p_Doc_Ref=48840-229-01

Looks like HOM also gives the option of a 4-space breaker

 

[calc30]

Thanks for all the help it is much appreciated.

Unless needed for code, I was going to install the sub panel in the garage, so the panels are back-to-back. And, the combiner box in the garage and feeds the CTs through the conduit into the main panel so there is no extra work. Plus, I don’t want to cut into the faux brick.