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Thanks everyone for your time. I have been taking in as much as possible for this forum as my off grid solar has gone through its first year, I live at a latitude of 41 degrees in Tasmania with very short sun hours in the winter and have a lot of questions. My system consists of 6 x 325w (2kw) panels on a vertical tracking frame running into a 150/45 victron regulator charging 12 x 2v 450ah FLA batteries in series. The batteries are second hand and the capacity has been determined through a 10 hour discharge before purchasing, the main reason being I had/have little experience with FLA and don't want to trash a new set (yet).
one of my main questions refers to Sunkings suggestions for "max smoke charging" and my personal observations, this winter unless it is raining, my panels are capable of supplying 1.3kw for 4 hours 10pm-2pm, although I know this is not technically sun hours. I have experimented with staying with default charging recommendations (28.8 absorb, 27.6 float) and also along rolls and sunking suggestions with higher, constant current charging of 29.6-30v with hydrometer as feedback.
what really gets me is I use on average 1-2.5kw of power a day, at an absorb of 28.8v in winter my charger is able to reach a current of 5-7 amps before switching to float for an hour or two before lights out. assuming I am able to reach 1-2%c on float before the sun sets (which absorb already has), can I assume my batteries are actually getting charged properly or is this smoke and mirrors? the hydrometer has only gotten to 1.23 once with 4 rainy days in a row and generally start at 1.265-1.27 in the morning and all sit at over 1.28 at sunset (temp compensated)
is running a single voltage constant current still advisable as charging hours is something I'll never have in winter, or can I get away with this, all the signs seem OK. both methods my solar can sustain but in this situation what approach will last longer, the voltage also holds well, in the morning, bank voltage is usually 25-25.4 under load (inverter, small fridge). I find it a little difficult to control max smoke and feel I might be doing it wrong, maybe a break down would be helpful, do you let the current taper off once voltage is reached or do you go into float as soon as voltage is reached, to prevent gassing all day long at ++volts.
one of my main questions refers to Sunkings suggestions for "max smoke charging" and my personal observations, this winter unless it is raining, my panels are capable of supplying 1.3kw for 4 hours 10pm-2pm, although I know this is not technically sun hours. I have experimented with staying with default charging recommendations (28.8 absorb, 27.6 float) and also along rolls and sunking suggestions with higher, constant current charging of 29.6-30v with hydrometer as feedback.
what really gets me is I use on average 1-2.5kw of power a day, at an absorb of 28.8v in winter my charger is able to reach a current of 5-7 amps before switching to float for an hour or two before lights out. assuming I am able to reach 1-2%c on float before the sun sets (which absorb already has), can I assume my batteries are actually getting charged properly or is this smoke and mirrors? the hydrometer has only gotten to 1.23 once with 4 rainy days in a row and generally start at 1.265-1.27 in the morning and all sit at over 1.28 at sunset (temp compensated)
is running a single voltage constant current still advisable as charging hours is something I'll never have in winter, or can I get away with this, all the signs seem OK. both methods my solar can sustain but in this situation what approach will last longer, the voltage also holds well, in the morning, bank voltage is usually 25-25.4 under load (inverter, small fridge). I find it a little difficult to control max smoke and feel I might be doing it wrong, maybe a break down would be helpful, do you let the current taper off once voltage is reached or do you go into float as soon as voltage is reached, to prevent gassing all day long at ++volts.
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