I have the following:
- My house with 400a service
- A pond subpanel 300 feet away from house fed from 100a breaker
- A barn 500 feet from pond subpanel currently run by a 12v offgrid solar system that has become unreliable due to shading during winter and long periods of cloudy days other times. This system draws 5 watts idle, 50 watts with everything on.
- A driveway gate system 1000 feet from barn currently fed from separate grid meter, but power company considers this a "commercial" account, and there are $40 in base charges per month (plus $1 of usage charges). This system draws 30 watts idle, 400 watts with gates actuating.
All of the "feet away" stuff is generally in a straight line starting from the house and ending at the driveway gate.
The $40 base fee from the power company has always burned my britches, and now with the issues I'm having with solar at the barn, I'm thinking it's time to run some power from the house.
Considerations:
I'd like to do this as cheaply and easily as possible, as the main reasons to do it are saving time and money, so the more money and time it takes, the less it makes sense to do...
I like the idea of GFCI protection, mainly for going through the pond. It would be very difficult to go around the pond, so I'm figuring I'll go through it by laying the cable on the bottom. There is already wiring through the pond for a fountain and an irrigation pump. I feel like GCFI is a necessity for this part of the run. So I figured just install a GFCI breaker at the pond subpanel at the start of the run ... well, I read that even runs as long as 300 feet can cause nuisance GFCI trips due to capacitance, and my run after the pond panel is 1500 feet. So how do I use a GFCI breaker to protect people from the pond wiring without having nuisance trips? How do I GFCI in segments? Is the only way using a transformer at each segment to isolate it from the previous segment? Or can I untie the grounds at each segment and use separate grounding rods at each segment, or something like that?
I was figuring I'd just run UF 12/2 in 200-500 ft segments, buried 12" deep and GFCI protected. Rent a little trencher from Home Depot and knock it out in a day. One segment goes all the way to the barn, and I'll tap the run to the driveway gate in several places to add receptacles along the driveway, if nothing else than to provide a places along the run to test for connection in the case of connection issues. But I'll have issues with the GFCI and length again, won't I? I've heard about GFCI Class C that is more resilient, but I can't seem to find these breakers for sale, especially that fit in a standard subpanel (seem to be DIN-rail mounted?).
I think I'll have a good bit of voltage drop: Voltage drop: 19.06 Voltage drop percentage: 15.88% Voltage at the end: 100.94
I'm just not too concerned about the voltage drop. Should I be? I know lighting does fine with a voltage drop. Other stuff has done well for me also in the past. I had thought doing the run at 240v do reduce current and step it down with a transformer at the gate, but then I wouldn't be able to tap the run with receptacles, and I'd have to bury 24" per NEC requirement.
What other kind of issues do you see?