I am trying to plan a stand alone system, and for that I will need a charge controller. I am looking at a few models from the company MorningStar. I have understood what MPPT is, and decided to not use MPPT because of the cost.
Currently I am looking at their series, ProStar, which they themselves call a "mid-range solar controller". Datasheet.
Below is a screenshot from the datasheet, which is relevant for my question:
I do understand that each type of battery: gel, sealed and flooded, have different specifcations. I plan to use a deep cycle gel battery. And I do understand the temperature compensation. I also understand the load disconnect and load connect voltage thresholds.
What I don't understand are the different stages of the charging. I believe it is called a charging algorithm, even though the data sheet does not use that word. Am I right?
Here is what I think I understand. But please correct any misunderstanding I have.
1) Full charge: When the insolation is not enough for the solar panels to reach the optimal charging voltage, it charges with whatever voltage is yields. Of course this only happens if the battery is below some voltage threshold where it is safe to charge. But which threshold?
2) PWM regulation: The insolation is so intense that panels yield a voltage greater than what is good for charging, in which case the voltage is reduced, using PWM. I think it must be charging with the "Regulation voltage", since regulation means changing (increasing) the charge/voltage of the battery.
3) Float: When the voltage of the batteries is at the optimal level, it should not be "regulated" any longer, but instead just maintained at that level. So I guess it charges with the voltage that is also the maximum healthy voltage for the battery. I think this number is what they call "Float".
4) Equalize: I don't know what this does, please teach me!