Avoiding charging during thunderstorm

I am in the process of installing a 9.4 kW PV system and thanks to this thread I researched whole house surge protectors. They all pretty much wire in next to your circuit breaker box requiring a hole to be cut in the drywall and a short run of wire through the adjacent stud to the breaker box.
Most are in the $100 to 200 range plus installation. I’m bundling mine in with the solar install. My electrician friend said if I cut the hole and drilled the stud so all he has to to was the wiring that he would do it for his service call fee.
I picked the Intermatic Smart Guard IG2240-IMSK because it has user replacable TPMOV modules, so if you get hit with the “big one”, you just replace a module for $40 each instead of the whole unit and an electrician’s bill. A little more upfront at $212 but you save later if it takes one for the team; it’s quick and easy (and cheap) to fix.
Here’s a link to one on Amazon.
https://www.amazon.com/Intermatic-IG2240-IMSK-Intermatic-Smart-Guard-IG2240-IMSK-Whole-Surge-Protector/dp/B00SBC0LTE/ref=asc_df_B00SBC0LTE/?tag=hyprod-20&linkCode=df0&hvadid=193994910693&hvpos=1o3&hvnetw=g&hvrand=10495662245897464213&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9014273&hvtargid=pla-313511123733&psc=1#featureBulletsAndDetailBullets_secondary_view_div_1537970191493

I love this forum. All y’all have saved me so much money on so many levels. Although here you’re making me spend money, but it will save me in the long run.

 

Kentuckyken and others:

I installed an [Correction: not Eaton ,but Leviton 51120-1] whole-house surge protector (no reason to favor that over others, but nice to have). Some things to think about especially if you are the one cutting the hole before the electrician comes:

-Download the installation instructions before you cut the hole. Most of the surge protectors don't have a specification regarding which breaker position they get connected to in the panel, BUT they do specify surge protector be as physically close as possible to the breaker that it is connected to. (Keeps [edit: IMPEDANCE] low, and response time by the protector quick, if the wires from breaker to the surge protector are as short as possible).

-These usually get attached to a high-amperage, dedicated two-pole breaker. Can be smaller amperage, or not dedicated, but they work better if high-amperage breaker. And MUST be two-pole, full-size (not half-height) so that it protects both phases of the main.

-Combined: suggests you should prepare your hole in a space that's right next to two adjacent unused breaker positions (for the two-pole breaker to go there, and then the wires to be as short as possible). (It would be particularly nice if there was an available 1/2" knockout there as well in the side of the box, so the wire doesn't have to wander off on a tangent to find a way through the box (or your electrician doesn't have to cut a new knockout in the box). If your main panel is mounted in the wall, you can only tell this by removing the cover, however.....which may not be in your comfort zone)

Example: installation instructions in: http://www.eaton.com/Eaton/ProductsServices/Electrical/ProductsandServices/Residential/SurgeProtection/CompleteHome/index.htm#tabs-2 , under "Documentation/Technical Data", the "Recommended installation practices"

Note that I am NOT an electrician nor licensed. You should listen to your friend and/or any other electrician before me. (I did, however, work for several years for an electrician, covered by his license as a helper, doing this kind of thing, so I have a bit of knowledge.....though you know what they say about that).

Edit: As I read this document again I just notice that they recommend twisting the conductors, 1/inch. Sigh. Back to the panel. Edit 2: The Leviton instructions didn't recommend this, interestingly.

 

I would strongly suggest thinking about investing a little more and check out the MidNite arrestors.
http://www.midnitesolar.com/products.php?productCat_ID=23

I am having second thoughts about my $70 whole house protector installed in the circuit box.

 

The following may or may not be the most economical choice in the long run, but if you want to put all the onus on your utility you can have surge protection installed at the meter. Duke Energy in the Carolinas appears to charge about $45 for the install and $7 a month, also noting that they will fix electrical grounding issues during the install (not including cable/phone issues). This would have the advantage of putting the protection right at the entry point and the utility is responsible for repairs, but on the other hand you have an additional $84 a year for as long as you keep the service (there's a 2 year minimum with Duke).

I did note this in the FAQ:


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