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Old 12-20-2013, 08:06 AM   #10
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Whistledoc's Avatar
City: Florence, Alabama
Country: USA
Vessel Name: Annie
Vessel Model: Homemade 53
Join Date: Jan 2012
Posts: 35
Thanks for the input. This how I arrived at 30 amp charger. Refrigerator is pulling 185 watts which equates to an amp and a half of 120. That equates to 15 amps of DC. Allowing for inefficiencies ...say 20 amps of DC. With a duty cycle of about 30% I am puliing 6 amps of power per hour out of the bank or 6 x 24 = 150 amp hours in a 24 hour day. Assuming I can cram all 30 amps of the charger into the battery each hours, that leaves me charging with the noisemaker a minimum of 5 hours a day. So I would say all of you are correct.

In actuality, I looked in the electrical storage area and found a spare 30 amp charger still in the box so I in stalled that just to get the system going. Had nothing to do with mathematics or numbers. It was what I had. But it seems that you all (here in Alabama we say "y'all" be confused with the nautical tern "yawl") are correct and I can ask Santa for a bigger charger for Christmas.
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