Advice on Dual Sol-Ark 15k w

[REFLEX]

Hi all, been a lurker for a few years finally got my permits for my Install so wanted to bounce some questions to those knowledgeable folks out there for the easiest/cleanest way to do this. I feel I have a relatively basic system, but we'll see.

- Live in Ojai, Ca on 5 acres, we have a 400 Amp service entrance panel on the exterior of the Garage. 5 years ago we put in a Generac, 16kw Guardian Generator which was connected to a Generac 200 Amp Smart Automatic Transfer Switch (inside the Garage) which includes a 20 circuit Load Center in one unit (Model RXGW20SHA3) and has our critical loads on it.

- We are installing 24kw (3 Sinclair Ground Mounts of 20 panels each), and that will go into 2 pcs of Sol-Ark 15k units which I intend to install next to the Generac 200A ATS. After we get this current permit finaled will will upgrade to have 12 kW of Battery Back up for this system. But again, I will do the Batteries AFTER we obtain the FINALS on this current system.

I had a Single Line Diagram done last year when I applied to get my NEM 2.0 (which I thankfully got). The SLD image is below and generally represents the system.

But here is where I have some questions.

1- I assume I can simply tie the Sol-Arks into the Generac 200A Panel as Circuits as shown below via the breakers, or is there a better way? Perhaps not using the Circuit Breakers?

2- The next question that the one that confuses me a little. When we get around to adding the Batteries (3 months later).... and if the Power goes out..... I assume I won't want the Generator to do the Auto Transfer and Power the Critical Loads anymore, but rather the Generator should be used for Charging the Batteries, is this correct? And in that case I assume I have to then rewire the Generator feeds to the Sol-Arks to charge the batteries?

Any assistance is very appreciated.

 

[Sennen]

With 2 or more inverters, I think a chargeverter would better suit your generator to directly charge the batteries Rather than pass through an inverter.

 

[REFLEX]

With 2 or more inverters, I think a chargeverter would better suit your generator to directly charge the batteries Rather than pass through an inverter.

Thanks, that makes some sense I will have to look at that option.

 

[Oldphile]

Your diagram won't work for 2 reasons.

1) Assuming the bus bars in the Generac panel are rated 225 amp, the NEC 120 rule will only allow a single 70 amp breaker for solar back-feed. This will limit your allowed PV production to 13,440 watts. You should connect the grid terminals of the Sol-Arks to the disconnect side of the AC disconnect.
2) This is diagram is grid tied only. Your batteries won't be powering anything. If you move the Sol-Ark grid connection as I've suggested you could disconnect the generator and connect the load terminals of the Sol-Ark where the generator was. However, I don't know how the Sol-Ark would control the transfer switch. Is this a Generac EZ transfer switch? If so, there's an easy solution.

 

[REFLEX]

Your diagram won't work for 2 reasons.

1) Assuming the bus bars in the Generac panel are rated 225 amp, the NEC 120 rule will only allow a single 70 amp breaker for solar back-feed. This will limit your allowed PV production to 13,440 watts. You should connect the grid terminals of the Sol-Arks to the disconnect side of the AC disconnect.
2) This is diagram is grid tied only. Your batteries won't be powering anything. If you move the Sol-Ark grid connection as I've suggested you could disconnect the generator and connect the load terminals of the Sol-Ark where the generator was. However, I don't know how the Sol-Ark would control the transfer switch. Is this a Generac EZ transfer switch? If so, there's an easy solution.

1- Thanks for bringing that up with the with the NEC 120 rule. I submitted this drawing with my plans and it passed Building and Safety... but I actually didn't want to go through circuits like this.

To clarify, when you say "connect to the Disconnect Side of the A/C Disconnect" ... theorhetically I could connect to the Cables inside the ATS and bring those out the bottom of the ATS to the Sol-Arks Grid Connect?

Also would I need the stand alone A/C disconnect I have on my drawing since the Generac has the 200A fused Disconnect on it?

2- This Generac unit does not have the Generac EZ switch. I don't know if that it adabtable to this ATS or not, I will have to check. But your idea about connecting the Sol-Ark Load to the Generator connector seems interesting, and perhaps I could call sol-ark to see if they have a solution.

 

[REFLEX]

Here is a picture of my ATS... if that assists anyone to answer questions.

 

[Oldphile]

1- Thanks for bringing that up with the with the NEC 120 rule. I submitted this drawing with my plans and it passed Building and Safety... but I actually didn't want to go through circuits like this.

To clarify, when you say "connect to the Disconnect Side of the A/C Disconnect" ... theorhetically I could connect to the Cables inside the ATS and bring those out the bottom of the ATS to the Sol-Arks Grid Connect?

Also would I need the stand alone A/C disconnect I have on my drawing since the Generac has the 200A fused Disconnect on it?

2- This Generac unit does not have the Generac EZ switch. I don't know if that it adabtable to this ATS or not, I will have to check. But your idea about connecting the Sol-Ark Load to the Generator connector seems interesting, and perhaps I could call sol-ark to see if they have a solution.

Yes you can connect inside the AC disconnect.
You need a manual AC disconnect to open the grid connection to the Sol-Ark. The ATS won't do that.
The only Generac load center with ATS that I've seen is with the EZ transfer switch. I guessed that this is what you have.

I'm going to revise my thinking on where to connect the Sol-Ark load terminals. Connect the load terminals to the grid terminals of the ATS. Then you can leave the generator connected as is. Grid goes down, Sol-Ark with batteries powers your load center until it shuts down due to low battery. Then the generator starts and switches the ATS. With the generator powering the loads, you can charge the batteries through the Gen Input of the Sol-Ark.

AC disconnect-------grid terminals (Sol-Ark) load terminals--------grid terminals (ATS) gen terminals------generator