Quote:
Originally Posted by stevehull
Where,
The only thing that I would change on the panels is the connector, the MC-4 which is now the standard.
Have you seen any age degradation with your panels (lower peak power or lower peak daily energy)?
Whew - those Weigman fiberglass boxes are pricey! Take a look at this Carlon box from Home Depot at ~ $12
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In my 1AM stupor, I mistakenly noted those panel/inverter connectors were Tyco when they are in fact MC4 (now that I compared the two). I edited my post above to correct that.
Day to day, year to year PV output has so many variables that I cannot see any degredation. I'm sure it's there, because I believe the textbook science that says the output degrades 1% per year, but the palm tree that shades my array part of the day also grows taller each year. You'll note when I post my monthly data on the 12.5kW thread, I provide previous years data for comparison.
My house came with one of those Carlon boxes buried in the front yard as a junction box, it takes on water. I used a similar carlon box in my attic out of the weather, but for the roof I wanted something more robust. I drilled the Wiegmann box where I needed cable gland entrances, that's not a problem. They're uniform thickness fiberglass side walls and a forstner or spade bit went right through them.
Quote:
Originally Posted by stevehull
Bottom line - make sure your neutrals on your big junction boxes coming in from the utility are tight to the lug . . . .
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There is a torque specification for the main lugs, sub-panel lugs, and the terminal leads coming off the breakers in most UL panels. However, most everyone seems to overlook that, and torque "to feel" without a measuring device. When I pulled out my torque wrench with the appropriate end bits and asked my AHJ inspectors if they wanted to check the torque of any of the bolts or lugs during my final inspection, they chuckled, said "If you
a) know they are supposed to be torqued, and
b) are offering us a tool to check them, then we expect you have torqued every one of the connectors to spec. Most homeowners don't know there's a spec, and most contractors develop a 'feel' for what's right and don't actually use a tool. Kudos for reading the NEC and knowing there's a specification for that." I had purchased the micro-torque wrench to torque the panel mount nuts on the racking to properly ground the WEEBs, it only made sense to torque the wiring connections if I already had the tool. I have heard electricians say they occasionally see lugs loosen over time, especially in areas with drastic temperature variations. The intense heat developed by arcing from a loose lug or loose meter blade terminal connection has been one of the concerns as smart meters were rolled out to consumers in my power utility. When the arcing caused a fire, consumers automatically blamed the "new smart meter" for the fire. I'm sure a fire marshal would properly diagnose the origination point for the fire if an inspection were performed.