Before we first decided that we would like to go solar for our electricity I had been living off grid for about fifteen years with no electricity at all. I had the Mother Earth News to keep me company thanks to one of my brothers. Its not easy but like everything else in life humans learn to adapt. I learned to adapt. Humans adapted too living with electricity, but somehow I dont see humans, in mass, every learning how too live without it again. This goes for fossil fuels, and nuclear energies as well. Over 6,000,000,000 humans. Pity about Earth.
One of the best investments I feel that we made concerning the use of photovoltaics was a subscription to HomePower magazine. Another bit of literiture was a book called the Solar Electric Independent Home book availible at New England Solar Electric Inc.. There is also the National Electrical Code book, it can be found at most home building supply stores. Of course it goes without saying that "it would have been better if you had studied on; electricity, electrical wiring, and photovoltaics sooner" but its never too late to start studying on this stuff.
As for the EGC or Equipment Grounding Conductor, most PV modules will have an extruded aluminum frame and somewhere on the back of that frame will be a hole made specifcally for the EGC. It may have a green screw, it may just a little sticker next to the hole that indicates it is for the EGC. Per NEC the EGC on PV module frames must be continuos. In other words, if you have all 9 modules together as one array and one module had to be removed for some reason or other, the EGC would still have to be in place between all of the remaining modules. I am not sure about the rules in your area concerning Earth ground rods but in my area it is an 8 foot rod driven in flush to the ground and a second one is only needed if the first one is not enough. One rod has to be proven though, so most contractors have started driving two, 6 foot apart. 2 rods dont have to be proved. Also if the power from the PV array is to go into a structure with an existing EGC to Earth, even if its in the form of the 120 vac from the inverter, that EGC on the modules will need to by carried through with the positive and negative leads and bonded too the existing EGC in the structure.
There are too many variables to go through in this forum to give an acurate detailing of how to set up and wire the system you would need to in place. Espeacially an NEC legal one that would give at least twenty years of trouble free service. It really should have a the personal attention of at least a licensed electrictian familar with Art. 690
For a short time I drove an 18 wheeler as well, only I hauled 8,400 gallons of gasoline three or four times a night. My insights on that are defensive although they might sound offensive. One must operate a motor vehicle on the highways as though every other driver on the road doesnt have a clue as too what they are doing. That they cant see any farther than their hood ornament and are totally oblivious too whats behind them. Its a sad thing that I should have that attitude but its what works.
Having a green job would be nice. I would rather be installing photovoltaics, but where photovoltaics are concerned in my area of North Carolina its desolate, espeacially when compared to some where like California. In time I suppose.
Gasoline is lighter than water, so ya it was an eighteen wheeler. The change of jobs came because the pay was lousy. I made better money rigging awnings. Thats where I assited in my first PV array installation. It was an earlier (1992 I think) installation that converged solar electric with the grid as well as adding asthetic side walk shading, all on commercial space. I have been hooked ever since. Thats about the time I decide to become an electrician as well.
There was a time when we used the pickup truck to provide battery power for the house by way of deep cycle batteries. Mostly lights. A family has a way of growing. Then a hurricane struk. There are so many down here I dont even remember its name, it blew over a hugh Hickory nut tree that was shading the house most of the year and I took that as a sign, so to speak, and started a PV array to charge the batteries. That system has grown as well. Then the flood waters of hurricane Floyd took out the back up generator, but instead of replacing it we spent that money on more PV instead. So now 100% of our electricity comes from the Sun, hence Sunourelectric.
Its funny that you should mention snow. As I type its snowing here.
12/2 NM-B would carry the current of one of your 51 watt PV modules but the jacket is not rated for outdoor use. If you had to use 12/2, 12/2 UF would be a better choice. But I dont recommend either. I dont know how the inspectors are in your jurisdiction but there is a good chance that 12/2 "Romex" of any type would not pass. Maybe if the PV array was out away from the house, pole mounted for example, they might let you use 12/2 UF from each module to a combiner box where each circuit is protected by a fuse or breaker and the wires are straped to code. Its not likely though because they generally dont allow Non metallic sheathing ("Romex") to de used on anything but wood, or dirt and wood if its UF rated and then it has to be buried to a depth of at least 24 inches. Even when UF has to go through brick or concrete it must be protected with at least a piece of PVC conduit and if the PVC is exposed at ground level it would need to be schedule 80.
This forum is not the best place to enlist advice on electrical work to be performed by a home owner. One really has no way of knowing who they are taking advice from.
There is a reason why we have;
the National Electrical Code,
state licensed electrical contractors that are bonded and insured,
and localized electrical permiting and inspections.
Have you ever been read the Riot Act?
Essentially it says that "if one person is allowed to a thing, then another will want to do it and then another and another and then the next thing you know we have a riot on our hands."
This where governments and laws come into the scene but then it starts all over again when governments and laws are manipulated by speacial intrest groups with lots of campaign monies to donate.
World without end, pity about Earth.
http://www.eere.energy.gov/consumerinfo/heatcool/hc_state_comm.html
As for spelling and grammer and all that stuff, thats the real reason I started visiting and participating in these online forums. It gives me the opportunities to exercise my writting and typing skills and since Renewable Energies is one of my favorite subjects, the Alt-E forum fits the bill. Thanks Alt-E
These figures are all just examples. There are so many varibles to all of what I have written. So dont take these caculations as the final word.
Seek out a qualified electrician near you. See if you can make a trade for his services. Mostly to assist you with sizing and typing the; wire, fuse's, disconnects, and all that will conduct, controll, or condition the electricity. The concern is that the system will at times be unattended and if there is a problem during those time it can protect itself. Check out this link.
http://www.sandia.gov/pv/docs/Design_and_Installation_of_PV_Systems.htm
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