Mate3S programming for 12v system

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My RE system: 1,000 watt PV array
Outback FLEXMax 80
Outback VFXR 2812 inverter/charger
8 - 6v Trojan L16RE-B (370 AH per battery @20 hr rate)
Generator (2,000watt and 6,000 watt)

Mate3S programming for 12v system

Post by Bfrenchsea » Sat Jan 04, 2020 12:29 pm

Newbie still trying to learn. Thanks in advance for your help. For our weekend cabin, I recently upgraded our 12v system with the Outback inverter/charger in my signature line. I also added the Mate3S and hub to program the system. I’m not sure that I have programmed my system correctly though because the bank doesn’t seem to be charging (from the generator) as it should.

In the winter we don’t get much sun and so rely on generator power to charge our batteries. My main question is if I have a 6,000 watt generator running into the Outback inverter, why are there only 700 watts being used in absorb phase? I would have expected more. If I’m wrong and 700mis right, I should stop wasting fuel with the 6,000 watt generator and use the 2,000 watt, right? Seems like a no brainer.

My bank also goes from 12.7 volts (after resting for a week) to 12.5 volts after only an hour or two of very light use (12 volt lights and inverter for modem). This seems like a fast drop. Would battery temperature be the cause? They are at about 55 degrees when we first get to the cabin.

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Gwendoly Espe
Applications Engineering
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Re: Mate3S programming for 12v system

Post by Gwendoly Espe » Mon Jan 06, 2020 11:58 am


You shouldn't see 700W the entire time, but you may see it at a point in time during the charge cycle. It looks like in your AGS settings, you are using only Voltage Start. Once the batteries reach the target voltage, it will take less energy/power to maintain it there. The current (amps) to the batteries should taper off as to not overcharge them and raise the voltage above the target.

Your Charger Absorb Voltage is 14.8 V

So your generator will complete the entire cycle even though it might be inefficient towards the end of the charge cycle.
Gwendoly Espe
Applications Engineer

Alpha Technologies Inc. / OutBack Power Technologies
3767 Alpha Way Bellingham WA 98226 USA

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