MPPT and PWM
A Solar or wind, charge controller, is the device used to regulate the flow of volts and amps being pushed into a battery or battery bank from a solar panel, windmill, Or other source of electrical energy generation.
The MPPT Charge Controller is known for the ability to down convert voltage while up increasing the amps to give you as much as 30% more power from a solar array that is normally lost when using a common or non MPPT controller.
Example: A solar module with a 17.2 volt Vmp would be pulled down to the battery voltage If the battery was at 11.7 volts using a common non MPPT charge controller. A loss of 5.5 volts or 32%. This means, if you have 1000 watts in solar modules, you just lost 320 watts. That would pay for an MPPT charge controller with money left over.
PWM Charge (pulse width modulation)
Helps to remove buildup on the plates in a battery extending a battery’s life.
All three of the above types of charging are used at the same time to charge faster and clean the plates. When the battery is low on charge, PWM will pulse longer with at a higher modulation. As the battery fills up it will pulse shorter with a lower out power level
Solar Controllers are engineered to keep you from damaging your batteries and should be used in every setup no matter how large or small the system. This is done by adjusting the power from the charging source based on how much power is required to bring the batteries up to full charge. This is done in three stages. Equalize, Bulk, Absorb and Float charge, and not in any written in stone order. Charge controllers can and do change directly from float charge to bulk or equalize as needed.
A good brand of controller may cost a little more, but well worth the extra cost. To get the same power output using PWM or a non MPPT charge controller., You will need extra solar modules which will take up more space on your roof and cost more.
Here are some good MPPT controllers from out webstore.