Open DC Breaker during Thunderstorms as Precaution?

[bt77]

Having gone through many threads on the subject, most agree that in case of a direct lightning strike on ground mounted panels (or even in their close vicinity), there is not much that can be done to save them and that they would most likely be fried.

So if we can't really rely on protection equipment in the extreme event of a lightning striking the panels, would it then be a logical move to at least open the DC breakers during bad weather with thunderstorms and cut the connection between the panels and the inverter, at least saving the latter for sure? Of course it could work the other way around, too. Like if the lightning strikes the house, electrical panel and the inverter, at least there would be no physical connection all the way to the panels, except for the grounding conductor from the electrical panel to the solar panel frames.

 

[timselectric]

1st line of defense is SPD's on all circuits entering the house.
But, it doesn't hurt to turn off the breaker. Odds are that you are not producing any power in a storm, anyway.

 

[bt77]

1st line of defense is SPD's on all circuits entering the house.
But, it doesn't hurt to turn off the breaker. Odds are that you are not producing any power in a storm, anyway.

OK. Yeah, there are SPDs, too. But alright, I guess it makes sense to turn off the DC breakers when there is very bad weather and thunders. Anyway we usually get thunderstorm weather here at night. So there is no solar production anyway. Open breaker from the panels will make no difference in that sense and the battery can still deliver power.

 

[Brucey]

With a direct strike I'm thinking the lightning would bridge the air gap in the open breaker and carry on through?

 

[Steve_S]

Turning off breakers won't accomplish much as that will jump the circuit...
Ground Mount Solar arrays do need to have their frames & rails grounded... This is for Lightning only and NOT an electrical ground.
The AC Systems as well as the DC system (Inverters & such) also have to be properly "electrically" grounded. There can be NO Ground Loops !
SPD's are needed on the DC (from solar panels) & AC input sides. NOTE there are several makes/brands BUT the most recommended are from Midnite Solar.

Link Here. They also have good videos & docs discussing it.

Category Products - MidNite Solar's

MidNite Solar Category Products.

www.midnitesolar.com

 

[JRH]

Having gone through many threads on the subject, most agree that in case of a direct lightning strike on ground mounted panels (or even in their close vicinity), there is not much that can be done to save them and that they would most likely be fried.

So if we can't really rely on protection equipment in the extreme event of a lightning striking the panels, would it then be a logical move to at least open the DC breakers during bad weather with thunderstorms and cut the connection between the panels and the inverter, at least saving the latter for sure? Of course it could work the other way around, too. Like if the lightning strikes the house, electrical panel and the inverter, at least there would be no physical connection all the way to the panels, except for the grounding conductor from the electrical panel to the solar panel frames.

I dislike lightning… Need to outlaw it..

 

[timselectric]

Ground Mount Solar arrays do need to have their frames & rails grounded... This is for Lightning only and NOT an electrical ground.

These parts must be electrically grounded for personal safety.
Lighting protection is never connected to what you want to protect. It's built above and around what you want to protect.

 

[bt77]

Turning off breakers won't accomplish much as that will jump the circuit...
Ground Mount Solar arrays do need to have their frames & rails grounded... This is for Lightning only and NOT an electrical ground.
The AC Systems as well as the DC system (Inverters & such) also have to be properly "electrically" grounded. There can be NO Ground Loops !
SPD's are needed on the DC (from solar panels) & AC input sides. NOTE there are several makes/brands BUT the most recommended are from Midnite Solar.

Link Here. They also have good videos & docs discussing it.

Category Products - MidNite Solar's

MidNite Solar Category Products.

www.midnitesolar.com

Thanks. I have SPDs on DC and AC.

I don't think being grounded for lightning is a thing though. Direct strike on the panels will kill them, no matter if they are grounded or not.

About the lightning overcoming the air gap at the breaker and jumping all the way to the house, yeah perhaps. But I still think having the breaker open is better than having it closed. Especially if it's night time and there is no solar generation anyway.

 

[bt77]

I dislike lightning… Need to outlaw it..

Yeah, difficult to outlaw it but I will check with my insurance company if I can add the solar panels to the house insurance policy and what that actually means (fried by lightning is covered?) They had asked me if I had solar panels when I first got the insurance and at the time my answer was no. So will check what is covered.

 

[JRH]

Yeah, difficult to outlaw it but I will check with my insurance company if I can add the solar panels to the house insurance policy and what that actually means (fried by lightning is covered?) They had asked me if I had solar panels when I first got the insurance and at the time my answer was no. So will check what is covered.

You better tell em ….and document that fact in writing in a way that you can demonstrate they were aware and didnt object or have concerns ……they rascal are better than a big fishing worm at wiggling……..