Forum Discussion
jrnymn7
Jan 20, 2015Explorer
How does C-rate play into all of this?
For example, my 280 watts of 12v panels have a combined Isc of 16a. Let's say that drops slightly to 15a.
On my bank, that's... 430Ah / 15a = ~ C/28
When charging at a C/4.8 rate, I see a switch from constant current to tapering current at ~83% soc. So at C/28, wouldn't that keep either controller in bulk/cc very deep into the charge?
If so, shouldn't mppt have the advantage (panel temp aside) throughout nearly the entire charge, even without any added loads, seeing as my bank can accept over 30a at 90% soc and a Vabs setpoint of 14.8v?
Moreover, wouldn't solar charging Lithium have the same effect, as they can accept huge amounts of current well into the charge?
For example, my 280 watts of 12v panels have a combined Isc of 16a. Let's say that drops slightly to 15a.
On my bank, that's... 430Ah / 15a = ~ C/28
When charging at a C/4.8 rate, I see a switch from constant current to tapering current at ~83% soc. So at C/28, wouldn't that keep either controller in bulk/cc very deep into the charge?
If so, shouldn't mppt have the advantage (panel temp aside) throughout nearly the entire charge, even without any added loads, seeing as my bank can accept over 30a at 90% soc and a Vabs setpoint of 14.8v?
Moreover, wouldn't solar charging Lithium have the same effect, as they can accept huge amounts of current well into the charge?
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