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Had a need to time the solar driven pond pump(s)... handy item out here at camp run a muck ....
my approach is to power as much as I can in stand alone solar systems using small panels, 80 amp tractor batteries and old recycled 12 volt car batteries to drive 12 and 24 volt loads.... white led's can be had for 3 cents each.....
low voltage easier to snake in without a permit as well
http://www.amazon.com/Amico-Digital-Power-Programmable-Switch/dp/B008999RYY/ref=sr_1_1?ie=UTF8&qid=1376465711&sr=8-1&keywords=12volt+timers
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Awesome -- I've been using something a bit more expensive.
Has anyone actually challenged County "authority" around NEC section 70?
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When I went to Waterworks about a month ago theyhad a sale on 12 volt pump with 3.4 gpm for $200. Also had 24v boasting 4.5gpm for $340. Just starting to research prices so I don't if that's cheap but I rather save for the 24v- seems more versatile.
I think the only dc loads I going with is a freezer and water pumps connected to 2 235panels with no batts. I want the pumps to raise water from a ground tank to a higher small tank and have gravity fed water at night. Does it make sense- just my pipedreams in my head??
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Some tidbits.
470W for freezer and water pumps is possibly overkill.
Gravity-fed water will pressurize at 0.42psi per foot of drop; you will need at least 20-30' elevation to get usable pressure, you will want to oversize the plumbing to avoid the friction losses.
I would add at least a small amount of battery for some lighting at night.
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I like Rule pumps - use a 25 watt 12 volt 500gph for circulation and the 60 watt 2800gph for transfer - these are very good pumps. They are primarily designed for marine applications - read direct drive - so they need appropriate pre filters and need to be fused properly - much cheaper to replace the fuse than the pump if something gets caught in the impeller
http://www.xylemflowcontrol.com/rule/
connectors - I reverse the "pattern" to keep the 12 and 24 volt systems from being able to be miss connected - keep things idiot proof. Makes the install all clean and modular note that the NEC does not approve the MC3 as it doesnt have a positive lock - no great shakes for garden path lighting...... seems more water proof and easier to handle from my experience however.... each his own.
http://www.tritec-energy.com/images/cont...eb_enu.pdf
bonus link; cheap fuses and fuse holders:
http://www.taydaelectronics.com/fuses.html
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Thanks guys so is HydraAir the distributor i have to remember that.
I plan for a batteryless offgrid system- maybe that's why I can't find a electrician to sign off. I have 6 235w panels. 2 panels is for a closed dc system powering a Sundanzer freezer and water pumps. If 470 w is overkill maybe I can save for extra pumps? Remaining 4 panels to be hooked up to the house with a Xantrex inverter. I was thinking don't need so many panels if not storing in batteries for night use. i going run the washer on this system weather permitting. When don't have sunlight going use the generator I ordered from HD online. They said it would take 4-6 weeks to arrive at the store. Mine took exactly 6 weeks for pickup. So now gotta electrician to hook it up to the house. Only has 1 110v MSW outlet so gotta be careful what I use it for.
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I really like batteries in a solar circuit - in not for storage - to even out the loads ...
as much as I complain about swapping out lead acid - I can get 10 plus years out of a us battery or trojan 6 volt golf cart battery
have used the big d8 - tired of blowing out my back - otherwise those would be my first choice, should be plentiful (cheap) out here in big diesel country.
added link to a 12 volt cut out circuit - I need three at 50-75 each thought I'd build my own bought parts for 6 for 22 dollars.....
http://www.learningelectronics.net/circu...la_18.html
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I do have a charge controller and trying to figure out if any harm in using it without batteries.
But at least 1 bugga who thinks like me only thing smart enough to make it work-
http://www.wind-sun.com/ForumVB/showthre...p-on-Solar