Parallel Solark 15k, no interconnect agreement.

[ImAnIdiotPleaseBePatient]

Don't have a house quite yet for the solar build, but I'm putting together my parts list so I can get started when I get the keys. All I have to offer is my parts list and a picture of my unfinished home ?

Parts list so far with est pricing:

TOTAL SOLAR PARTS LIST

BIG STUFF:
Solark 15k x2 $17200
18650batterystore batterys (catl302ah x 96, jbd16s x6, bms breaker x 6) $11505
Qcell Q.PEAK DUO ML-G10+ x64 $10000
PVkit2.0 racking $4200



DC BATTERY

4/0 15 feet black, 15 red, lugs $216
1/0 25 black 25 red might need a little more, no lugs $175
bluesea 1000 amp busbar need two of these and covers $600


AC SYSTEM
siemens 200 amp double throw transfer switch $1090
polaris 2 in 1 out =< 4/0 need six $240
2/0 wire in and out of solark prob 20' each color $200
4/0 service entrance cable 25' $245
48" wireway x 2 if i can join them $590

PV System

red wire 10 gauge solar $400
180' of 1 1/4 emt $360
Guesswork connectors for emt $360
PVKIT gripperfit, PVKIT2.0 etc

TOOLS

4/0 hydraulic crimper $87
ferrule crimper with ferrules $40
klein crimper for bms ring terminals $40
klein wire strippers $34
ratcheting cable cutter $130
mc4 removal tool $10
Extra mc4 connectors $22
4/0 lugs $25
1/0 lugs $15

Before tax credit = $49655
After tax credit = $34758

Hopefully I have a roof soon! I will keep this updated as I confirm small details like "why did I order this" and "why did china accept my international wire and not send me the stuff" and as the price hastily begins to climb. Trying to do this mostly to code, but Florida has this pesky rule that you have to be a "eelectricul contraktor" or something like that, so it will be off grid with a little assist from the grid. I feel like I have learned enough here to take the plunge, so I started really trying to plan it out a little better. Looking forward to warmer weather and a new project. Thanks everyone here for answering all my questions. If you have any tips, or any of the equipment looks like the wrong choice, I am all ears. A few things here and there will not be to spec, but I am trying to hit 95% or so.

 

[Ampster]

The SolArks have a built in transfer switch. Is there a reason you think you need that redundancy?

 

[ImAnIdiotPleaseBePatient]

The SolArks have a built in transfer switch. Is there a reason you think you need that redundancy?

I wanted to be able to have one side of the double-throw grid only with no sol ark, and one side with the grid going (only) through the sol ark, not tied together before the main panel. I figured this could help prevent the issue with some people having power go back to the grid. I don't know for sure, but it would be nice to "fully" isolate the Solarks from the grid, and not just at the breaker on the solark (still live power at the breaker).

Sort of a combination of the solark manual diagram for "solark 15k with transfer switch" and "standard parallel solark 15k"

 

[BentleyJ]

I wanted to be able to have one side of the double-throw grid only with no sol ark, and one side with the grid going (only) through the sol ark, not tied together before the main panel. I figured this could help prevent the issue with some people having power go back to the grid. I don't know for sure, but it would be nice to "fully" isolate the Solarks from the grid, and not just at the breaker on the solark (still live power at the breaker).

Sort of a combination of the solark manual diagram for "solark 15k with transfer switch" and "standard parallel solark 15k"

Yes, in the data center world its called a Maintenance Bypass so power can be diverted directly to the loads thus Bypassing and isolating the UPS systems for maintenance and service such that it is safe with no power inside the UPS cabinets at all.

 

[Ampster]

I figured this could help prevent the issue with some people having power go back to the grid.

I don't know much about that issue but it sounds like a user setting issue. What you would lose with a manual transfer switch is having the grid as backup and to be able to charge the batteries automatically if the solar was not sufficient. Have you looked into interlocked breakers which would be less expensive? That is what @BentleyJ referred to as bypass. That is not the same as isolating the Skybox from the grid all the time.

 

[ImAnIdiotPleaseBePatient]

I don't know much about that issue but it sounds like a user setting issue. What you would lose with a manual transfer switch is having the grid as backup and to charge the batteries if the solar was not sufficient. Have you looked into interlocked breakers which would be less expensive?

I shouldn't lose the ability, because when the double-throw is set to "solar", the grid is still feeding into the grid input of both solark, which enables peak shaving. In the other throw position, it will be grid completely bypassing the solark (not though the solarks bypass).

With regard to the zero export, there are people line-siding their connection with solark before the panel, x-ing out the grid export feature, and still exporting. My only connection to the grid when in solar mode will be the AC input of the Solark, so I'm hoping that it helps with that, rather than just pushing power into a grid-connected main panel and praying to the CT gods. If not, I'm gonna be in big doodoo with inspectors I guess.

 

[ImAnIdiotPleaseBePatient]

Yes, in the data center world its called a Maintenance Bypass so power can be diverted directly to the loads thus Bypassing and isolating the UPS systems for maintenance and service such that it is safe with no power inside the UPS cabinets at all.

Exactly.

 

[Ampster]

I shouldn't lose the ability, because when the double-throw is set to "solar", the grid is still feeding into the grid input of the solark, which enables peak shaving.

The grid input of the SolArk is bidirectional so you will still have to make sure the SolArk is configured for zero export. The redundant switch is still a lot more expensive than interlocked breakers would be. It is your money to spend any way you want? Just be aware that some maintenance tasks may require power to the SolArk. Firmware updates are one example.

 

[ImAnIdiotPleaseBePatient]

The grid input of the SolArk is bidirectional so you will still have to make sure the SolArk is configured for zero export. The redundant switch is still a lot more expensive than interlocked breakers would be. It is your money to spend any way you want? Just be aware that some maintenance tasks may require power to the SolArk. Firmware updates are one example.

I'm interested in the idea, but wouldn't that put me over the 120% rule for the main panel, if I had the solarks(~25600watts of solar) going into a breaker? Plus, with the interlock, it becomes either grid or solark right?

The way I am trying to set it up, it would be

Position 1) Grid only (normal house)
Position 2) Solark with grid assist.

 

[Ampster]

I'm interested in the idea, but wouldn't that put me over the 120% rule for the main panel, if I had the solarks(~20kw of solar) going into a breaker?

The 120% rule only applies to backfeed. With zero export there will be no backfeed. The SolArk will still be connected via a breaker to the main panel.

 

[ImAnIdiotPleaseBePatient]

The 120% rule only applies to backfeed. With zero export there will be no backfeed. The SolArk will still be connected via a breaker to the main panel.

But with the interlock breaker flipped to "solark" would I have the grid at the same time. Not sure I am understanding it. The normal way I understand an interlock is with a generator. It is either generator OR grid.

Are you saying they make some other kind of interlock? Either way, nice to know 120% rule doesn't apply.

 

[Ampster]

Are you saying they make some other kind of interlock?

The interlock I am referring to goes on the panel fed by the SolArk. It is a device that allows only one breaker at a time to feed that panel. One breaker is for grid feed and the other is for the SolArk output. Typically they cost less than $100 depending on the breaker panel.

 

[ImAnIdiotPleaseBePatient]

Oh ok, I think I am starting to understand now. So grid into the main panel breaker is one way, and the backfed breaker with grid going through the solark to the backfed breaker is the other position. So cool! I wonder if I could figure out how to install one ?

 

[ImAnIdiotPleaseBePatient]

The interlock I am referring to goes on the panel fed by the SolArk. It is a device that allows only one breaker at a time to feed that panel. One breaker is for grid feed and the other is for the SolArk output. Typically they cost less than $100 depending on the breaker panel.

So I guess I would need something like a 175amp breaker and the main 200amp breaker on the interlock. Can you go use both L1/L2 on an interlock like that? I would also have to see if I have enough room in the 200 amp panel to do this.

 

[Ampster]

I wonder if I could figure out how to install one ?

The devices come with directions. In most cases it is opposing breakers on a breaker panel.

Can you go use both L1/L2 on an interlock like that? I would also have to see if I have enough room in the 200 amp panel to do this.

You have to use double pole breakers to switch L1 and L2. Since you are in the planning stages, choose a panel with enough spaces which you will need for expansion in the future. However I just checked and the SolArk takes a 200 Amp breaker and that may preclude interlocked breakers because at that Amperage they may cost more than a three way switch. The diagram 2 in the SolArk 15k manual shows a manual bypass wired to the panel, the grid and the SolArk output and that may be your best bet. It will not change anything on the grid input to the SolArk so using that wiring plan will not solve your grid backfeed concern. You will still need to get the configuration correct to minimize that risk.

 

[ImAnIdiotPleaseBePatient]

The devices come with directions. In most cases it is opposing breakers on a breaker panel.

You have to use double pole breakers to switch L1 and L2. Since you are in the planning stages, choose a panel with enough spaces which you will need for expansion in the future. What size breaker does the SolArk 15k have on its output side?

I have two of them in parallel. Not sure, but the current can go up to 20kw on each one, so about 40kw worth of breaker plus that extra room you are supposed to have. Probably could get away with 175amp breaker for both I think for both.

The AC input breaker of each sol ark is 200amps, but I didn't even know it had one on the output. I was just going to join both together with a polaris and plug the combined wire into the 200amp breaker of the main panel.

If I have to do a change order with my builder for a new panel to accommodate the interlock though, it already negates all the cost savings with that alone. But if I can get it done with my regular 200 amp panel, I'm always down to save a penny.

 

[Ampster]

I did not see your earlier post showing Diagram 2 and how you are going to wire the manual switch. I had mistakenly assumed from your concern about backfeed that it was on the SolArk grid input. I think your switch is the best option and it is truly a bypass switch.

 

[ImAnIdiotPleaseBePatient]

I did not see your earlier post showing Diagram 2 and how you are going to wire the manual switch. I had mistakenly assumed from your concern about backfeed that it was on the SolArk grid input. I think your switch is the best option and it is truly a bypass switch.

It's all good. I learned a lot just back and forthing with you. I'm sure that interlock trick may come in handy some day. Cheers. I probably won't have many updates here for a month or two, but I'll keep checking in and updating my list when I realize what's wrong with it. Already changed the polaris connectors because I had the neutral setup wrong. But I'm not going to update it more than probably once every two weeks until stuff starts showing up at my door.

 

[Danke]

“15k x2 $17200”
$8,600 each?

Also, since you have two Sol-Arks, why the need for a transfer switch? Do you ever expect both of them to fail at the same time?

 

[ImAnIdiotPleaseBePatient]

“15k x2 $17200”
$8,600 each?

Also, since you have two Sol-Arks, why I need for a transfer switch? Do you ever expect both of them to fail at the same time?

No, I just like the idea of being able to bypass them to work on both of them and have full power to the house. I'm assuming maybe some shipping/tax or whatever on the price. A few items are just estimates.