2 ms·

>You have to sync to the grid ... > You have to provide ability for line workers to guarantee that you aren't back feeding power onto a line they had turned off

by coryrc 18y ago

>You have to sync to the grid ... > You have to provide ability for line workers to guarantee that you aren't back feeding power onto a line they had turned off ... Most solar inverters do this. It is very easy. They don't start adding power to the line until a little past a zero crossing, which solves both the sync issue and the line down issue. > Say that you're producing 10A of current with your little device. If your breakers are 15A breakers, now they won't trip until 25A of current is running through that circuit. Only partially true, depending on where you measure the amperage, but I doubt it'd be UL and/or NEC approved to be on anything but a dedicated circuit. If the device is the first thing after the breaker, then 25A could be flowing on the load side of the breaker. However, if it's the last thing in the circuit, the setup is completely safe. No way to assure this, of course, unless it is a dedicated circuit.

robotrout 18y ago
> start adding power to the line until a little past a zero crossing That sounds technically sound. Is it compliant with power company rules? The reason I ask is that I looked into setting up a wind generation business 20 years ago, building windmills in Wyoming and selling back to the power company. The power company required special "blessed" devices between user generation equipment and the grid to protect the grid. This usually took the form of sensing circuitry and a physical relay that could completely isolate the grid from your equipment if necessary. Doing everything in silicon with MOSFETS and algorithms is definitely technically feasible, but lacks the fail-safe behavior of physical isolation on demand. I'm surprised that they allow this.