Derating 24v Solar Panels?
I'm considering running two 250w/24v poly panels; tracked/pointed during spring/fall, and flat during the summer; thru the Tracer 3215BN 30a mppt controller. I can also get 200w/24v mono panels, local...
Forum Discussion
BFL,
o.k., so no tracking, but still bucking, when in pwm mode, hmmm.
But what about this?
"The input amps to the controller with an MPPT controller (in MPPT or PWM mode) is whatever it comes to when you divide panel watts by "panel voltage" The "panel voltage" is whatever the controller chooses at the moment. In MPPT mode it will choose Vmp. In PWM mode it will choose a voltage (which will be higher than the Vmp for MPPT) that provides the amps to match the "demand" on the output of the controller."
...if the controller is not tracking in pwm mode, how does it "choose" a voltage? Or do you mean to say, it will simply allow panel voltage to match Vbatt + Rcirc, and then divide watts by that voltage for amps?
I've noticed that when there is a large drop in power (due to clouds), the controller will quite often continue/resume at a lower voltage than before the power drop, once the clouds have passed.
o.k., so no tracking, but still bucking, when in pwm mode, hmmm.
But what about this?
"The input amps to the controller with an MPPT controller (in MPPT or PWM mode) is whatever it comes to when you divide panel watts by "panel voltage" The "panel voltage" is whatever the controller chooses at the moment. In MPPT mode it will choose Vmp. In PWM mode it will choose a voltage (which will be higher than the Vmp for MPPT) that provides the amps to match the "demand" on the output of the controller."
...if the controller is not tracking in pwm mode, how does it "choose" a voltage? Or do you mean to say, it will simply allow panel voltage to match Vbatt + Rcirc, and then divide watts by that voltage for amps?
I've noticed that when there is a large drop in power (due to clouds), the controller will quite often continue/resume at a lower voltage than before the power drop, once the clouds have passed.
