Generac Generator + SolarEdge Inverter

[arf88]

If that is the case they should not have an option for "Homeowners" support as an option. There is uncertainty from the installers so either i put my faith in their hands or get an understanding myself.

In any case waiting to hear back from the solar company but i think all indications show there needs to be change from the existing solar install to make this work.

[Mike90250]

Setting the generator speed for 61 Hz will not affect anything other than clocks, which would run a tiny bit fast. It would be "wrong enough" that the inverter should ignore it, being outside the 60.00Hz spec.

[arf88]

I wish that was possible but it is not. None of the settings let you adjust this.

[N4KIT]

I had similar generator concerns when we were planning our installation, however in our situation the generator is a "critical loads" instead of "whole house". The generator is 8kW portable, so cannot possibly handle the whole-house loads. The solar system is SolarEdge, 9kW of panels and a 7600H inverter. It feeds the main panel through a 30A breaker. The inverter is also battery-ready although we do not yet have the batteries.

In preparation for the solar install, I moved 8 "critical loads" circuits (well pump, refrigerator, chest freezer, furnace air handler {furnace is LP}, 1 LR receptacles circuit, 1 kitchen receptacles circuit and the microwave) into a Generac HomeLink 6853 transfer switch/sub-panel, which gets it's grid-side feed from a 30A breaker in the main panel.

Set up this way, once we have the batteries installed, we have three options:

1. "Normal" - Transfer panel is in grid mode, grid power feeds the main panel, inverter is feeding main panel and main panel feeds the sub-panel. Batteries being charged if needed.
2. "Solar-backup" - grid power is out, transfer panel is in grid mode, batteries are feeding both the main and critical loads transfer subpanel.
3. "Generator" - grid power is out, transfer/critical loads panel is in Generator mode. Inverter, main panel and grid are isolated from the critical loads panel which is now being fed by the generator.

I realize this is different from the OP's situation in that it is not whole-house, automatic and does require user intervention.

IMHO, the only safe way to accomplish the whole-house, automatic transfer situation being discussed is to have the solar installer move the inverter feed to a line side tap instead of MSP breaker feed, and insure the ATS for the whole house is installed between the inverter taps and the main panel, as others have described. If your inverter does not have an over-current protected disconnect other than the MSP breaker, one will need to be installed (most jurisdictions require a separate disconnect outdoors so first responders can shut the solar down externally).

Offered for the benefit of the group

20190619_155548.jpg

[arf88]

Thanks for sharing, I agree with everyone else, things needs to be moved. I'm waiting for my solar company to let me know if the electrician can do it or they need to do it to maintain the warranty. Sadly they don't have experience with generators, my first conversation with them, they thought everything could be left alone and work but they just didn't know any better. Mind you these are all licensed and pros but i can't blame them since they focus on their own equipment.

[arf88]

Let me ask you guys this, still waiting to hear back from the solar company, but how critical is that 30A breaker? Going with the way everyone recommended it would eliminate the 30A breaker in the loop, unless they require to put another sub-panel just for it which would add more cost.

This is what I sent them.

[ButchDeal]

Let me ask you guys this, still waiting to hear back from the solar company, but how critical is that 30A breaker? Going with the way everyone recommended it would eliminate the 30A breaker in the loop, unless they require to put another sub-panel just for it which would add more cost.

This is what I sent them.

you need a fused disconnect. It would not pass code without a fuse or breaker.

[Markyrocks69]

Yep. If you look at the drawing I posted it has a fused disconnect between the solar inverter and the connection point to the grid.

[arf88]

There is a disconnect there but I don't recall if it is fused. Likely not which is why they put the 30A breaker in. This means the disconnect would have to replaced or another sub panel added to add the 30A fuse back in. Joy

[Markyrocks69]

There is a disconnect there but I don't recall if it is fused. Likely not which is why they put the 30A breaker in. This means the disconnect would have to replaced or another sub panel added to add the 30A fuse back in. Joy

You maybe able to use like an individual circuit fuse box (if such a thing exists) or a fused air conditioning disconnect (which is like 12-15$... ) inline with leaving the existing exterior disconnect alone. You will probably want to verify all this but the existing disconnect maybe too far away. Theres rules on how far a tap circuit can go b4 it needs a ocpd.

that being said as long as there is an exterior disconnect whatever you put inline shouldn't need to be accessible from the outside of the house.

I was dealing with similar issues. I had considered something like this.

https://www.homedepot.com/p/GE-60-Amp-240-Volt-Fused-AC-Disconnect-TF60RCP/100134720

I had planned on a subpanel the entire time and it was basically installed already so I did end up using a tap to feed the subl and just putting pv breakers in there.

[N4KIT]

Two issues:
1 - positive disconnect outside. This is for the protection of first responders.
2 - overcurrent protection. This is to protect the equipment.

In my installation, the installer put in a small NEMA 3A rated box outside. Inside that box is a double pole 30A circuit breaker. This is in addition to the 30A breaker in the main panel. So in essence I have 2 circuit breakers in that one line.

If the outdoor disconnect on your system has a handle on the side, open it up and it will have either a pair of large buss fuses OR a plastic bar with a little handle on it. If it is the plastic bar (no fuses) then it does not have overcurrent protection other than the breaker in your main panel, in which case it would need to be swapped out. Some (most?) of this type disconnect can be retrofitted with a fuse block, which would solve that problem with relatively little cost.

If the outdoor disconnect does not have a handle on the side, again, open it up and you will find either a double pole circuit breaker or again the plastic bar with handle.

If you can post a picture with the cover open, we can probably tell you if that disconnect has overcurrent protection.

HTH,
Chris

[arf88]

You maybe able to use like an individual circuit fuse box (if such a thing exists) or a fused air conditioning disconnect (which is like 12-15$... ) inline with leaving the existing exterior disconnect alone. You will probably want to verify all this but the existing disconnect maybe too far away. Theres rules on how far a tap circuit can go b4 it needs a ocpd.

that being said as long as there is an exterior disconnect whatever you put inline shouldn't need to be accessible from the outside of the house.

I was dealing with similar issues. I had considered something like this.

https://www.homedepot.com/p/GE-60-Amp-240-Volt-Fused-AC-Disconnect-TF60RCP/100134720

I had planned on a subpanel the entire time and it was basically installed already so I did end up using a tap to feed the subl and just putting pv breakers in there.

I was thinking something like this because of the space constraint it would be easiest to just rewire and swap out the old switch rather than adding more switching and more conduit.

https://www.homedepot.com/p/GE-30-Amp-240-Volt-Fusible-Outdoor-General-Duty-Safety-Switch-TG4321R/202978635

[arf88]

Two issues:
1 - positive disconnect outside. This is for the protection of first responders.
2 - overcurrent protection. This is to protect the equipment.

In my installation, the installer put in a small NEMA 3A rated box outside. Inside that box is a double pole 30A circuit breaker. This is in addition to the 30A breaker in the main panel. So in essence I have 2 circuit breakers in that one line.

If the outdoor disconnect on your system has a handle on the side, open it up and it will have either a pair of large buss fuses OR a plastic bar with a little handle on it. If it is the plastic bar (no fuses) then it does not have overcurrent protection other than the breaker in your main panel, in which case it would need to be swapped out. Some (most?) of this type disconnect can be retrofitted with a fuse block, which would solve that problem with relatively little cost.

If the outdoor disconnect does not have a handle on the side, again, open it up and you will find either a double pole circuit breaker or again the plastic bar with handle.

If you can post a picture with the cover open, we can probably tell you if that disconnect has overcurrent protection.

HTH,
Chris

Thanks Chris, it has a handle for sure for the emergency disconnect. I can't recall off my head but I'm 90% sure it is not fused and just a bus bar. So i was thinking of something like this

https://www.homedepot.com/p/GE-30-Amp-240-Volt-Fusible-Outdoor-General-Duty-Safety-Switch-TG4321R/202978635

[Markyrocks69]

Thanks Chris, it has a handle for sure for the emergency disconnect. I can't recall off my head but I'm 90% sure it is not fused and just a bus bar. So i was thinking of something like this

https://www.homedepot.com/p/GE-30-Am...321R/202978635

That will definitely work. However how far away is the existing switch from the main panel? Bc as I said tap rules are tricky. If the switch is within 10 ft you're golden.

If it's over 10 feet but less than 25ft the wire between the tap point and the ocpd needs to be rated to handle at least 1/3 the amps as the service entrance cables to the house. So if the service entrance cable can handle 200 amps the wire would need to handle 66.66amps so that's like 4 gauge which I doubt is the size of the wire ran now.

If it's over 25 feet the disconnect/ocpd needs to be as close to the point of the tap as possible.

[arf88]

That will definitely work. However how far away is the existing switch from the main panel? Bc as I said tap rules are tricky. If the switch is within 10 ft you're golden.

If it's over 10 feet but less than 25ft the wire between the tap point and the ocpd needs to be rated to handle at least 1/3 the amps as the service entrance cables to the house. So if the service entrance cable can handle 200 amps the wire would need to handle 66.66amps so that's like 4 gauge which I doubt is the size of the wire ran now.

If it's over 25 feet the disconnect/ocpd needs to be as close to the point of the tap as possible.

How about this one, it looks the same, wonder why such the price disparity?

https://www.lowes.com/pd/Siemens-30-Amp-Fusible-Metallic-Safety-Switch/1000036089

Sorry forgot to respond to the distance question previously, the existing switch is about 1 ft from the main panel and 1 ft from the inverter, everything is in very close proximity. If I can just swap things and it works than I can use the conduit run from the existing switch to the main to the ATS and just route it through the existing and new ATS conduit instead unless that is against code.

The solar company gave me the green light to have the electrician do the work so they don't have to come out but I told them i want it in writing that this change does not affect the warranty so waiting on their email tomorrow for confirmation.