What is a solar charge controller?
A solar charge controller, or solar charge regulator, is an important instrument in almost all solar power systems that use batteries as a chemical energy storage solution. It is used in stand-alone or hybrid solar power systems but not used in straight grid-tied systems, which don’t have rechargeable batteries.
Its two basic functions are very simple:
- Prevents batteries from overcharging
- Blocks the flow of reverse current.
Overcharging can result in battery overheating, or, in an extreme possibility, a fire. Overcharged deep-cycle flooded batteries could also emit gas of hydrogen, which is explosive. What’s more, overcharging will quickly ruin the battery, thus shortening its lifespan dramatically.
Solar charge controllers can preclude the flow of reverse current from batteries to solar panels at night when the voltage of solar panels is lower than that of batteries.
Furthermore, solar charge controllers have other optional features, such as battery temperature sensor & compensation, Low-voltage disconnect (LVD), Load control (dusk to dawn), Displays, remote monitoring and diversion load control.
Let’s dive into the article to check these functions & features one by one.