They're not supposed to be grid-forming and should turn off if there's no grid voltage. And if you turn off a breaker you should always check that there's no voltage, you might've turned off the wrong breaker.
That's good then. Although I hope they also considered what happens if there's two of them on a circuit, because if the mains power goes off, but there's another panel on the same circuit, they'd each see the other's voltage on the line, right?
And yeah, you should verify that a circuit is de-energized after you flip the breaker, but I've seen both some real weird electrical work, and some electricians who aren't that careful.
They generate no frequency so the situation you fear is not possible.
The panels themselves are DC, but there's an inverter feeding 120V 60Hz (or whatever) into the wall, right?
Yes, but it's a system that is designed to sync with the frequency of whatever other electricity is out there, and it shuts of if the main shuts off. Almost all rooftop systems without a battery in the US are set up the same way.
Still, it's important to check that things you think are disconnected do not have current flowing through them. And this makes it more important.
Pure sine wave or modified? Modified (square wave) are not good for electronics, particularly computers.
They're not supposed to be grid-forming and should turn off if there's no grid voltage. And if you turn off a breaker you should always check that there's no voltage, you might've turned off the wrong breaker.
That's good then. Although I hope they also considered what happens if there's two of them on a circuit, because if the mains power goes off, but there's another panel on the same circuit, they'd each see the other's voltage on the line, right?
And yeah, you should verify that a circuit is de-energized after you flip the breaker, but I've seen both some real weird electrical work, and some electricians who aren't that careful.
They generate no frequency so the situation you fear is not possible.
The panels themselves are DC, but there's an inverter feeding 120V 60Hz (or whatever) into the wall, right?
Yes, but it's a system that is designed to sync with the frequency of whatever other electricity is out there, and it shuts of if the main shuts off. Almost all rooftop systems without a battery in the US are set up the same way.
Still, it's important to check that things you think are disconnected do not have current flowing through them. And this makes it more important.
Pure sine wave or modified? Modified (square wave) are not good for electronics, particularly computers.
The answer likely varies by model. Check.
The regulations allow only for one. If you want a bigger install than that you need individual approval I think.