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Discussion Starter · #1 ·
I've been looking all over Sailnet and searching the web, and could use some input form the experts/experienced people here.

I'm setting up my fourwinds wind generator and plan to add solar eventually. The boat will be unattended for days at a time, so the wind gen will need a dump load. (No one there to tie the tail off the wind or throw a stop switch.)

Ideally, the system would have these features:

Accept power from
1) wind generator (fourwinds II)
2) Solar panels (maybe 500 watts eventually)
3) 2 x Engine Alternators (currently a separate one for starting, why not somehow put it to use when running the engine for charging?) I think means something that boosts to overcome internal resistanc eof the batteries.
4) Ideally shore power, although I have a 3-stage shore power charger in place already.

Battery Charging
1) House bank of 2x4D (eventually 4x4D) -- gel batteries
2) Engine starting battery -- wet cell
3) Temperature sensor to keep batteries happy

Inverter for 110v
1) 2500 or 3000 watts
2) remote on/off
3) Automatic switching from battery to shore power.
4) Ideally a way to separate off non-essential 110v if the shore cable comes unplugged. For instance, so the A/C doesn't drain the house batteries to zero when I'm away. (Not that I have A/C. It's an example.)

More
1) Handle dump load to water heater (2 cascading dump loads if possible)
2) Eventually measure and display amphours in/out/remaining in house bank

Anyone have any ideas if there is a single device that does most of this, or maybe a collection of devices that would do most of this?

Regards
 

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Discussion Starter · #5 ·
Thank you. That's what I'm now planning to get.
 

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Discussion Starter · #6 ·
OK, so after an afternoon with PowerPoint, dinner and then more PowerPoint, here's the design I'm thinking about. Green is for things I have already. Blue is for what I have to buy. Dotted lines are choices to make. Not sure where to route the House Bank alternator.



Any thoughts?
 

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Discussion Starter · #8 ·
Does the ACR go in like this?

 

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Discussion Starter · #9 ·
Nevermind. Google covered it.

Regards
 

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Discussion Starter · #11 ·
Thank SD. I'll google Echo Charger and see what that's all about.

I'm off to the boat shorty. I'm looking to measure the current solar panel between the davits to see what maximum size I could easily put there.

Oh and I bought a Xantrex C60. Thanks Chuckles!
 

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Discussion Starter · #12 ·
He'd only need the link 20, not the 2000, which is designed to control a Freedom series inverter IIRC.
SD, I'm planning to hold off on the monitoring side of things this year. I have other $$ priorities like the keel which is showing lots of rust. Would I be remiss in not having the monitoring this year? I figure that I can watch the volts to see if there is a tendency toward undercharging. Even if it isn't completely accurate due chargining and drain within 8 hours, there will be some rudementary precision (repeatability) that I can use to see a trend.
 

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Discussion Starter · #14 ·
After buying the Xantrex C60, I see that it doesn't do MPPT. Darn.

Anyone know if there is something similar on the market that does MPPT?

From Adrift at Sea » Solar Power on Boats:
An example*: Normally a 25 Watt panel will be outputting 1.39 amps at 18 volts. 18 volts is too high for the batteries to charge with, since bulk charging requires only 14.4 volts. With a normal three-stage controller, the excess voltage is shed as heat-that's why the charge controllers heat up so much. 18-14.4=3.6 volts-3.6 volts * 1.39 amp = 5 watts. So you're losing about 5 watts out of 25 watts to heat.

With a MPPT-type controller, it uses a high-frequency DC-to-DC converter to drop the voltage down to 14.4 volts, but increases the amperage to 1.74 amps at the same time. So, instead of getting 6.95 amp-hours from the panel for the day, assuming about five hours of full output, you get 8.70 amp-hours, or a 25% effective increase in amp-hours to the batteries. This makes a lot of sense, since you're basically recovering the 5 watts that was being lost to heating the three-stage, non-MPPT, charge controller.
 

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Discussion Starter · #18 ·
bene
I saw in your diag that you plan on an automatic switch for the shorepower/inverter. You sure you want to do that? if the shore power goes out you will automaticly switch even if you don't know or aren't there. and then your batteries could get drained and possibly damages if drained too far. Plus it's another fancy device that could fail more easily than a simple switch.
Good point Xort. I'm thinking things like the microwave could be plugged in to an always-on outlet. You've got me rethinking this a bit.

By the way, in showing the diagram to my wife, she said "I don't need a microwave." That changes a few things, like I can now use the 1000watt inverter that I already have. (Those big ones are expensive.) And I could take the microwave down - it blocks the view.
 

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Discussion Starter · #22 · (Edited)
Good perspective CD. I do want to make life easy for my family.

The water heater should be covered. It's the dump load or it's shore power. If the switch fails there ought to be no harm done.

I'm wondering why there isn't an inexpensive MMPT with dump load. (Other than the fact that it has the word "marine" in the product description.) Still noodling that one.

By the way, I appreciate all the great input. Finding all this out on Google would be exhausting.
 

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Discussion Starter · #27 · (Edited)
An inverter is not required with a 12v heating element.

Since we will be on the hook most of the time, I'm planning to eventually put in a 12v heating element, to replace the current 120v heating element. They do exist. the one I saw is 600W. I'll find a link if anyone wants it.

This will be for dump load only, which we might not see much of. At least when we get back to the boat, there might be hot water.
 

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Discussion Starter · #30 ·
No problem Christy.

By the way all, I read that fans don't run well as a diversion load. Something about the waveform. (Ok I could be more specific, but have other things to do just now than to look up the threee letter acronym.)

Of course, it's probably nothing a big honking capacitor couldn't fix.
 

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Discussion Starter · #31 ·
PWM -- Pulse Width Modulation.

Someone mentioned somewhere that PWM also interferes with ham radio reception. (That I believe, unless you put some capacitors in the right place.)

The Tristar has a switch on it to do PWM or "on-off" battery charging. See the datasheet here.

That probably fixes it. I didn't buy the Tristar, I have the Xantrex C60 on the way, but I'm still looking for a MPPT that handles a dump load -- sounds like an opportunity to capture the "wind and solar both" (a.k.a. "belt and suspenders") market.
 
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