1. What is a solar charge controller?
Solar charge controllers are mainly used in off-grid solar systems, off-grid systems mainly rely on batteries to store power, solar charge controllers are devices that regulate the transmission of power from the solar panels to the solar batteries, solar charge controllers regulate the current to prevent the ever-changing solar power current from damaging the batteries to minimize or damage the batteries, which is very important in a caravan or off-me system.
2. How the solar charge controller works?
First of all, you need to understand the solar panels throughout the day as the weather continues to change the voltage of the current in the circuit is also changing, the voltage of the solar panels due to most of the expected results can not be achieved so the rated voltage of 12V solar panels is just the average, the voltage during the day in the 11 ~ 15 or so fluctuating, and even at night the voltage is extremely low or zero, the second battery charging situation of the different battery voltages are also constantly changing. Changes, stable charging battery voltage of 12.7 volts or so, the voltage will reach 13 volts or so when fully charged.
Only the power supply voltage is greater than the battery voltage to charge the battery, and at night the battery voltage is greater than the solar panel and reverse current will occur. In order to ensure that the solar panel voltage and battery voltage want to check and balance the solar charge controller must be installed to ensure that the power supply voltage is greater than the battery voltage during the day when the full power to disconnect the power supply in a timely manner, the night to disconnect the circuit to ensure that the battery current will not flow to the solar panel, the battery for the circuit power supply to ensure that the current is stabilized.
3. Types of solar charge controllers
Solar charge controllers are mainly divided into two types of PWM and MPPT, then to the two types of introduction and purchase recommendations
(1) PWM solar charge controller,
PWM charge controllers are characterized by simple, cheap and suitable for small-scale solar power generation, the use of PWM must ensure that the solar system voltage and the battery voltage as far as possible to maintain the same or will cause power loss, PWM conversion efficiency is low and can only use lead-acid batteries.
(2) MPPT solar charge controller,
MPPT is the mainstream of the solar power system, he can use any form of solar energy system, than the conversion efficiency of the PWM about 30% greater than the use of MPPT you do not need to worry about solar panels and battery pack voltage match, it will automatically step down or step up, so you can increase the size of their own solar power generation, you can also choose the right battery storage location, without having to A lot of rows of battery cable lines, all at the expense of a higher price.
Purchase options, if you just use in RV travel and ready to make a poor trip that PWM just meet your needs, but you do not know the choice requirements are the use of the experience then MPPT can be a no-brainer purchase.
4. How to choose solar charge controller size?
Select solar charge controller is mainly based on the circuit current to choose, you need to know the power generation of the solar system and voltage according to the current = power / voltage, roughly estimate the current size, for small RV solar energy can be selected for the smaller current 8 to 10 amps PWM or MPPT charge controller, for the photovoltaic group must be selected MPPT, for example, 1000w48V solar system current is For example, 1000w 48V solar system current is 1000/48=21A, choose 25A or 30A rated current MPPT charge controller can be. In order to prevent the current increase can not choose 20A charge controller.
5. Price of solar charge controller
Solar charge controller according to the type you choose and use the maximum voltage of the solar energy system, the mainstream MPPT type of charge controller price in the 70 ~ 600 U.S. dollars, your system voltage is higher and need higher power charge controller price is naturally high, for the PWM charge controller price is only 15 ~ 40 U.S. dollars, the price is often associated with the function of the powerful.
6. Is it so that solar power need charge controllers?
No, for 100W solar panels need charge controllers, but for 10W and below solar panels do not need charge controllers, the battery allows lower current to enter and does not cause harm.
In conclusion,
The need for a charge controller is a must for solar charging systems that have a battery bank. A charge controller is a good way to regulate the power delivery from the battery to the solar panels.
