Best Location to Install Surge Protector for Solar Array

[Zeigh]

Hello,

Where is the best location to install a surge protector (Midnite MNSPD-600) specifically to protect a solar array with microinverters?

I will have an 18.47 kW system installed in a couple of months that I am preparing the wiring for it. All panels and micrinverters are routed directly to a combiner box (obviously), then to the utility net meter, then to the disconnect switch, and finally connected to the incoming utility grid. Since I have a "farm panel" (photo attached before reconfiguration) at the main meter outside, there are separate bus bars and my solar array will connect to one of them upstream of my entire main distribution panel for the house inside. There is already an existing whole house surge protector at the house panel.

So, is the best efficiency to install a surge protector for the solar system in the combiner box or next to the breaker where it connects to the utility?



Peace,
Dr. Z.

[Zeigh]

Farm Panel.jpg

[Mike90250]

I was all set to answer, till you said microinverters.
There is no effective way to protect microinverters or panel mounted optimizers with surge arresters.

Any direct or nearby strike at the array, is going to toast a bunch of stuff.

The only place you can place a arrester is at the DC combiner box at the base of the array, before it makes the run to the inverter ( optimizers or straight GT inverters or Charge Controllers)

or for microinverters:

At the Disconnect panel for the microinverters before it goes to the Main electrical panel (I guess that's the box shown in your pic.) Tha'ts unfortunate because any induced voltage, will be directed to the inverter panel, which is right next to your main panel. If you have a 1400' lightning bolt, the 12" to get to the juicy ground next door, is not going to be much strain for the surge to traverse.