Solar Charge Controllers
A Solar regulator aka charge controller is used with a stand alone or off grid solar power system or in a hybrid grid connect system with batteries, in a grid connect solar power system with no batteries there is no need for a charge controller.
A solar regulator takes the form of a smallish box shaped object with some solid state electronics inside and is installed between the solar panels and the deep cycle batteries that are to be charged by the panels. The role of the charge control unit is to monitor and control the amount of charge being sent to the battery bank and insure over charging does not occur, a regulator can also act as a power source on the circuit prior to the batteries allowing for the powering of some electrical appliances while the batteries are being charged. Modern solar regulators are highly efficient in their operation outperforming most 3 stage mains battery chargers.
Choosing The Right Solar Regulator
To find the correct size regulator required add up the amp ratings of all the solar panels in the array, this will show the minimum size charge controller needed for the system. Its not a bad idea to think of the future when purchasing a regulator as you may want to extend the size of your off grid system some time in the future so buying a larger regulator can save some money down the track.
Low Voltage Disconnect
Some charge controllers have a low voltage disconnect system built in (LVD). Battery life can be shortened if charge voltage drops below a certain level frequently, the LVD system prevents this from happening by monitoring battery power levels and automatically disconnecting the power supply should the level reach a critical low level, a good way to protect the life and health of a deep cycle battery bank and save you some money.
Maintenance Of A Solar Regulator
No maintenance is required for solar regulators with the exception of maybe checking the wiring for corrosion which is common on DC circuitry. A charge controller should me mounted in a cool dry place out of the weather and of course out of the reach of young curious hands. It is also good practice to have a fuse between the solar panels and the regulator to reduce risk of damage and fire risk.