Buck Gizmo -Volts vs Amps ? UPDATED
Update 5 Nov. (It didn't work out as hoped) I got my little gizmo, see close-up photos here http://www.ebay.com/itm/DC-DC-15A-Converter-Buck-Adjustable-4-32V-12V-to-1-2-32V-3-3V-5V-24V-Step-Down...
Forum Discussion
My contention is that the standard PWM solar controller is a straight buck converter with a lower intake rating (12v panels) than the buck converter in the standard MPPT solar controller designed to work with higher voltage panels (24v panels)
The standard MPPT controller can also do the lower intake 12v panels of course, like any buck converter can at less than its max rating.
The world is divided into "!2v" and "24v" panels where you must have an "MPPT" controller because it is the only kind that can buck the voltage from 24 to 12 to match the battery in an RV. People have taken this to mean you must have MPPT when in fact all you must have is the buck converter with enough intake rating.
I contend that the standard " MPPT" controller would do nearly as well without the MPPT feature, same as it does in Float when it is not in MPPT but it still bucks the voltage and gets more amps from the available input watts. You see this all the time when the battery only wants say 4 amps and you add a load of 8 amps, you can see 12 amps coming in from the solar controller that is NOT in MPPT at the time ( it is only in MPPT during Bulk)
The MPPT feature just fine-tunes the panel's output for the buck's input, but you still get some sort of panel input with no MPPT.
So I am calling the high intake rating buck converters a form of PWM solar controller that can do 24v panels and PWM is not just for 12v panels like the standard PWM controller is limited to.
The market will sell you a controller that is MPPT with a high intake buck converter you can set to 12v battery level for output. Nobody sells one of those without the MPPT feature.
IMO you can get one of these gizmos that will be a PWM 24v panel controller but for much less money.
The standard MPPT controller can also do the lower intake 12v panels of course, like any buck converter can at less than its max rating.
The world is divided into "!2v" and "24v" panels where you must have an "MPPT" controller because it is the only kind that can buck the voltage from 24 to 12 to match the battery in an RV. People have taken this to mean you must have MPPT when in fact all you must have is the buck converter with enough intake rating.
I contend that the standard " MPPT" controller would do nearly as well without the MPPT feature, same as it does in Float when it is not in MPPT but it still bucks the voltage and gets more amps from the available input watts. You see this all the time when the battery only wants say 4 amps and you add a load of 8 amps, you can see 12 amps coming in from the solar controller that is NOT in MPPT at the time ( it is only in MPPT during Bulk)
The MPPT feature just fine-tunes the panel's output for the buck's input, but you still get some sort of panel input with no MPPT.
So I am calling the high intake rating buck converters a form of PWM solar controller that can do 24v panels and PWM is not just for 12v panels like the standard PWM controller is limited to.
The market will sell you a controller that is MPPT with a high intake buck converter you can set to 12v battery level for output. Nobody sells one of those without the MPPT feature.
IMO you can get one of these gizmos that will be a PWM 24v panel controller but for much less money.
