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Corbet
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I currently have a group 31 Diehard Platium as my only battery. I'd like some sort of digital display panel I can mount inside for easy monitoring.
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So after receiving some Amazon gift cards for Christmas I ordered the Morningstar unit. Even if it's overkill now it gives me the ability to upgrade without rewiring a new unit in. Plus the 2nd battery option is appealing. Even if I never add a second battery to the camper I could hook the controller up to the truck and charge it's battery as well. That would be somewhat useful if I stay in one place a few days in high temps where the fridge in the truck is working hard. Give me options.
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You're on the right track. Were you able to source a good meter?
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Your battery, if it's a blue-cased beast weighing in the neighborhood of 75 lbs, is an Odyssey-made-for-Sears and as such requires specific absorption-phase and float-phase voltage setpoints. I don't know if your SunSaver Duo? is it? is adjustable. Your controller's manual will say.
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That battery can take up to and including 50 amps during a "bulk"-phase (but one won't see that with the mild input of a small solar array. I see just 13 amps going to the battery with a good, high sun angle) of a three-phase charge cycle which usually lasts to an 80% State Of Charge. The voltage set point for the *absorption*-phase (from 80% to 100% S.O.C.), according to Odyssey, should be 14.7 volts (not 14.4), and this phase should last from 3 to 5 HOURS at which point the battery when fully charged should be *float*ed at 13.6 (not 13.4, which is all that products like the Battery Tender will give).
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I have the same battery but am using the Morningstar SunSaver MPPT 15-L which has adjustable voltage setpoints as well as a time duration setting adjustment for the absorption phase. To do this requires a Morningstar interface and a Windows-based PC or laptop. I managed to stumble through the process only! with the help of Morningstar's help via telephone. It was a year ago, so I couldn't do it again if I tried... but the system works extremely well using two 100-watt panels connected in series for a nominal 24V input to the charge controller using 10AWG, then for the 20-INCH run from the controller to the battery I'm using 8AWG marine cable.
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Good luck to you. Hope you can charge that Odyssey-for-Sears Group 31 the way it needs to be charged (again, this is according to Odyssey).
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