Generac Generator + SolarEdge Inverter

[arf88]

I'm going to have a Generac whole house backup system put in, I have a solar system with SE6000H inverter. Is there anything that needs to be programmed or changed from the standard configuration to support having a Generac system put in?

The installer was wondering how the Inverter would handle the Automatic transfer switch if it detects voltage coming in from the solar if Edison cuts power. He is going to call Solar Edge but curious what you experts think and any feedback and info you might have which would be of value.

Thanks

[Mike90250]

If you don't have batteries, it's no big deal.

You have to not let the solar inverter see the power the generator produces, it may try to sync ( a whole house generator is large enough that it might actually fool the inverter and get fried with your 9Kw of PV panels.) and that would be bad. The installer should know this, if not, you may want a better educated installer.

[ButchDeal]

I'm going to have a Generac whole house backup system put in, I have a solar system with SE6000H inverter. Is there anything that needs to be programmed or changed from the standard configuration to support having a Generac system put in?

The installer was wondering how the Inverter would handle the Automatic transfer switch if it detects voltage coming in from the solar if Edison cuts power. He is going to call Solar Edge but curious what you experts think and any feedback and info you might have which would be of value.

Thanks

The inverter should be installed on the grid side of the ATS

[arf88]

That's the concern, the installer was not sure about solar being in the loop and how the inverter handles things.

He did pull the main panel off where the edison shore power was coming in so I believe he did mention it would be routed there which is where i suspect he will connect it to as that is pretty standard and on the grid side of the ATS.

Thanks guys, always lots of knowledge on this forum.

[arf88]

Explain something to me.

My solar company told me if I have batteries that there will also be a automatic transfer switch and that the PV system will charge the battery during the day. How is it that solar panels can charge the battery and there is no issues with the batteries being on the other side of the ATS?

If I'm putting in a Generac generator on the other side of the ATS would this not be an issue with the Inverter seeing the power generated by the generac generator and try to sync and get damaged?

[Mike90250]

Your installer needs to know this stuff before hand, and not learn at your expense. I know how to do it, but have not "done" it, since I'm off grid and have not proof tested any instructions I would be giving you, to give 2nd hand to your installer.

[arf88]

At this point it just self education for me to make sure i do my due diligence. The problem is not all installers are familiar with solar in the loop.

I did call SolarEdge and they said there is nothing that needs to be changed on the inverter itself b/c as the shore power goes out the inverter shuts off.

I also called my solar installer and they were pretty sure of the same thing but will confirm with level 2 tech at solar edge.

What i found out in terms of my own question about the powerwall electrical connectivity and how it differs from a Generac Generator is that there is additional electronics in which the Tesla electronics/switch communicates with the inverter turning it on and off as needed based on battery capacity.

[wanabee solar]

I have the inverter connected on the house(after the the ATS) side true a contactor what is in parallel with the ATS house contactor.
The inverter is only online when the grid power is present.

[arf88]

Thanks for the confirmation.

[arf88]

Spoke to the installer, and his concern was when the generator is running it is obviously supplying power to the main panel which has the Invterter Solar breakers. Is this going to cause a problem with the solar producing power and trying to pump it to the grid?

[Markyrocks69]

I wouldn't want to risk the generator and the inverter bumping heads in the electrical system. Its alot of money to be messing around with.

This is not that complicated. The ATS isolates the grid from the generator..... hook the inverter up to the grid side b4 the ATS so it isolates the grid AND the inverter from the generator.

You can also use some kinda relay that is normally closed but will open if it senses power from the generator feed circuit.

[arf88]

Believe me it does not sound complicated but it is and the installer has a valid question and concern no one is addressing.

Edison power goes out > Inverter shuts off

Now we introduce an ATS and Generator.

Edison power goes out > ATS kicks over Generator supplies power to the Main panel. The Main Panel has 30A Solar breakers which I assume once the Generator is powering up the entire Main Panel the Solar Inverter also powers up b/c of those breakers in the main panel? Do you see the dilemma here? If the inverter only turns on when Edison power is on that is fine but if the inverter is getting power through the main panel and the Generator is connected to the main panel does this not cause the Sync issue and problem described above?

[ziomeks]

I'm no genius at this as I too am a neubie, but the description you give makes this an impossible situation. The ATS has to select either Generator OR GRID / Solar to feed the breaker panel. With the solar system fused into the main breaker panel, I see only trouble on the horizon. It seems that this change over would be better served by a manual process on power fail.

[ButchDeal]

I'm no genius at this as I too am a neubie, but the description you give makes this an impossible situation. The ATS has to select either Generator OR GRID / Solar to feed the breaker panel. With the solar system fused into the main breaker panel, I see only trouble on the horizon. It seems that this change over would be better served by a manual process on power fail.

the solution is VERY simple. TAP the inverter into the lines on the grid side of the ATS. it is what is commonly called a line side tap. Do this instead of connecting the inverter to a breaker on the MSP.

[ButchDeal]

Believe me it does not sound complicated but it is and the installer has a valid question and concern no one is addressing.

Edison power goes out > Inverter shuts off

Now we introduce an ATS and Generator.

Edison power goes out > ATS kicks over Generator supplies power to the Main panel. The Main Panel has 30A Solar breakers which I assume once the Generator is powering up the entire Main Panel the Solar Inverter also powers up b/c of those breakers in the main panel? Do you see the dilemma here? If the inverter only turns on when Edison power is on that is fine but if the inverter is getting power through the main panel and the Generator is connected to the main panel does this not cause the Sync issue and problem described above?

It is REALLY simple. move the solar from the breaker on the MSP to a Line Side Tap, that is installed on the grid side of the ATS. Then what happens is

Power goes out
Inverter shut downs
ATS cuts off grid and inverter from MSP