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dual grid-tie systems

LazyAcres

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Is it possible to have 2 grid-tie systems ?
I currently have a 10kW SolarEdge grid-tie system and would like to add more capacity with a separate/new grid-tie system.

Can they both be connected to the same panel in parallel ?
Would they still shut down when the grid is off ?
 
Is it possible to have 2 grid-tie systems ?
Yes. But all grid-tie inverters operate by raising the V. If there is not enough usage in your line then can happen that the V goes up and they stop producing power

I currently have a 10kW SolarEdge grid-tie system and would like to add more capacity with a separate/new grid-tie system.

Can they both be connected to the same panel in parallel ?
Would they still shut down when the grid is off ?
Yes. Grid-tie must shut down. If you want power in a blackout you need an off-grid or hybrid system.
 
Yes. But all grid-tie inverters operate by raising the V. If there is not enough usage in your line then can happen that the V goes up and they stop producing power


Yes. Grid-tie must shut down. If you want power in a blackout you need an off-grid or hybrid system.
Thanks for your reply.

I understand that the grid-tie inverter produces a higher voltage than the grid to force the current into the grid.
Would a second grid-tie system not cause a race condition where they try to out-raise each other ? Is that what
you mean when you say: "not enough usage in your line", that is, the grid is not taking the current quickly enough ?

Also, how does the inverter sense that the grid is off when there is another power source (the other inverter) on the line ?
Would the second inverter not simulate grid power ?

BTW, I don't use the solar system for a blackout, I have a generator for that.

Thanks again for your help.
 
Not in California......10 kw maximum grid tie limit for residence....ALSO grid tie feed in cannot exceed 20 % of service panel capibility (in amps)
 
Not in California......10 kw maximum grid tie limit for residence....ALSO grid tie feed in cannot exceed 20 % of service panel capibility (in amps)
hmm ... I am in CA 50 miles north of Sacramento (PG&E) and not aware of the 10kW limit. My neighbor has a 13.2kW grid-tie system.
 
Thanks for your reply.

I understand that the grid-tie inverter produces a higher voltage than the grid to force the current into the grid.
Would a second grid-tie system not cause a race condition where they try to out-raise each other ? Is that what
you mean when you say: "not enough usage in your line", that is, the grid is not taking the current quickly enough ?
Yes. Here where I live the lot of Grid-tie PV systems become a problem.
Like a street connected to a transformer and having a lot of houses with PV. If the power consumption of the street is too low then V rises and the grid-tie inverters stop power generation.

Also, how does the inverter sense that the grid is off when there is another power source (the other inverter) on the line ?
Would the second inverter not simulate grid power ?
No because they do not have a sinus generator. They sit on the grid sinus. No grid, no sinus, no production.

BTW, I don't use the solar system for a blackout, I have a generator for that.
Me too and hate it. Loud. Using the off-grid inverter as house UPS.


Not in California......10 kw maximum grid tie limit for residence....ALSO grid tie feed in cannot exceed 20 % of service panel capibility (in amps)
Here in some EU countries 50kW (50kVA) is the max allowed :)
Local codes ...
 
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