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Old 03-20-2007
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camaraderie is a jewel in the rough camaraderie is a jewel in the rough camaraderie is a jewel in the rough
Susan...you obviously don't understand OHM's law very well and that is NOT a slam.Here's the deal.... As I said...the MAXIMUM output at 12V for a 100Watt solar panel is 8.33amps. This can't happen on your panels since they are rated at 17V so their maximum amp output is 5.88 amps at THAT voltage in direct sunlight.
The Bluesky is a great device that makes sure their is a good interface between your 17V panels and your 12V battery so that the MAXIMUM amperage is not lost. This means that the blue sky has the potential to get you CLOSE to the theoretical maximum of 8.33amps at 12V being delivered into your batteries. So...I don't doubt that you CAN see 8amps input on your panel at PEAK.
The other problem with maintaining this even if you could somehow maintain 8AMPS being delivered to your batteries is that your batteries will not accept 8 amps as they begin to edge over 80% charged. But that is a whole nother discussion. The point is that even IF you are able to get 8 amp instantaneous readings...you'd have to maintain that reading for 10 hours a day to get 80 amp/hours into your batteries. That is patently ridiculous unless you are near the equator in a cloudless sky with someone constantly tweaking the panels from 8AM to tropical sunset at 6PM.
So...hopefully that explains why you are TRUTHFUL when you say you see 8 amps and I am truthful when I say you cant get 80 a/h into your batteries per day. I am prepared to eat my words here if Practical Sailor says anything different.
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