When the Classic rolls the logs over at midnight it appears to switch the charge stage to Bulk MPPT no matter what. There is many times that our system floats all afternoon and night because the wind turbines keep the bank voltage above the Rebulk voltage setting. When the sun comes up the next day and provides extra power from solar to bring the bank from Float MPPT back to Float - that's what it should do is continue floating until the bank is discharged sufficiently to re-bulk and absorb it again.
Because of the reset of the charge stage, it will re-bulk and absorb the bank again the next day due to the reset to Bulk MPPT charge stage at midnight, when the bank doesn't need it. I have to monitor this and manually force it back to Float when this happens to prevent over-cooking batteries that are already well-done.
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Chris
Chris
You are correct the Classic considers Midnite the start of a new day and there fore starts a new charge cycle. What you need is End Amps but with multiple controllers that is an issue. The new current sense module would fix this though so give us a little bit and we will see if we can fix this for you.
Of course in the interim you could change the clock times so it thinks midnight is say at 8 or 9 pm so you are not getting up at midnight to force a float
That current shunt will be the first thing I buy when you get it done. ;D
I don't have to get up at midnight and force it into float because it's a rare occasion (except in winter) when the turbines will put out enough power to re-absorb the bank. They normally just meets loads and keep the bank floating, and it only happens when we get several good solar insolation days in a row. So in the morning when I see the bank has been floating all night, even though it says "Bulk MPPT" on it again, I just force the Float for the day and everything is fine.
I already tried the end amps, but with solar and wind on networked controllers there's some problems with that because the wind controllers can "fool" the solar controller into thinking the end amps has been reached. And the wind controllers can also "fool" the whole works into dropping into float because the wind dies down.
Yep, the Whiz Bang, or whatever you call it, will totally "fix" it. The voltage will climb very rapidly when it tries to re-absorb, the amps will go way down, and it will drop the system back into Float. That will be nice because we can take a five day fishing trip and not have to worry about the batteries getting all the water cooked out while we're gone :)
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Chris
Hi Chris,
with the latest firmware you can now set 'days between bulk'.
Discussed here: http://midniteforum.com/index.php?topic=1541.msg13022
--vtMaps