What are the main functions of the solar charger’s & inverter’s
There are many components to a solar power system, but two of the most important are the solar charge controller and the inverter. These two items are absolutely vital to the operation of the system.
The Charge Controller
A charge controller is necessary because it prevents the batteries from overcharging. Every solar panel converts the power of the sun into electricity. The more sunlight there is, the more power the solar panels produce. Batteries aren’t designed to take large power fluctuations, however, and they can only hold so much charge before they break down. The controller regulates the power flow that is sent to the batteries and keeps them fully charged, so they are ready to be used when they are needed.
All batteries have a three-stage charging process: Bulk, Absorption and Float. The batteries draw the most current during the Bulk stage. After the batteries reach a certain level of charge, usually 14.4-14.6 volts, the current tapers off but the voltage is maintained while the batteries charge. Once the batteries are charged, the voltage must be reduced to 13.4-13.7 volts and the batteries have to draw a small current to maintain the charge. A controller automates this cycle and makes certain the batteries are never damaged by being overcharged. It is installed between the solar panels and the batteries.
The Inverter
Solar panels produce electricity in the form of low voltage direct current (DC). Most modern appliances operate using 120 volts of alternating current (AC). There are special appliances available that are designed to operate using the DC produced by solar panels, but any standard appliance will require the use of an inverter.
An inverter is an ingenious little device that changes direct current to alternating current. It also steps the voltage up to 120 volts. Three kinds of power inverters are normally used on solar power systems today: square wave, modified sine wave and true sine wave inverters. The names refer to the shape of the current ‘wave’ that is produced by the inverter; a sine wave is considered to be best.
Square wave inverters are the cheapest. They are limited to 500 W of power. They are also rough on equipment, because the wave shape is so far from the ideal. Modified sine wave inverters are slightly more expensive and produce a wave with a shape between that of a sine wave and a square wave. Most equipment and appliances will run on one, but computers and anything with a timer or a motor speed control mechanism will not.
True sine wave inverters are the ideal. They are also the most expensive of the three kinds. They will run any kind of equipment, and some are computer controlled.