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Old 21-06-2010, 05:51   #1
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Upsizing Alternators on Yamaha 9.9hp Motors

Hi I'm seeking advice, I'm in late stages of build a fast light low profile open 12.5 m cat she will be powered by twin 9.9 hp Yamaha outboards Has anyone used a bigger than supplied alternator on one of these successfully. Given outboards im tight on power generation which is fine for day sailing regatta sailing. I want outboards for simplicity and no props in water.

The boat is a cabrio style bit like SIG 45 so is designed to convert to go cruising when I will need more power generation. major loads ...fridge, Tiller pilot, nav computer. So then I add more solar say 400 watts of panels an Air breeze wind gen Even then not much reliable power.

I look at Honda 2Kva generator as backup but it seems the charging on this for say 300AH will take forever given low output. I think 8A at 12 v or similar at 240V. Am i right or am i missing something. Hence my question welcome experienced responses.
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Old 21-06-2010, 06:51   #2
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A 2,000 Watt generator will power a 100A ➛ 120 Amp 12V (nominal) battery charger.
(2,000W max. x 0.85 = 1,700W cont.) 14.2V = 119.7 Amp
Gord May
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Old 21-06-2010, 20:20   #3
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using AC output via 100Amp or so charger gets me there

I was planning to use an Inverter Charger So I need to make sure that said Charger can handle loads of up to circa 120Amps. Then I plus the A/C output from generator into charger and i will be able to top off Batteries faster, assuming the batteries can handle that charge rate.

Im hoping to cruise Australia northern half, Indonesia, Phillipines, Thailand area, Im probably going to need to take charge from 110 to 250 a/c sources, any suggestions of a good Inverter charger setup that will suite?
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