Ifyour shopping for a charge controller for your solar panels, then youmay have crossed a term called Low Voltage Disconnect (LVD), everwonder why the prices of charge controllers that have LVD are higherthan controllers that don’t have the LVD feature?
Obviouslypeople who buy charge controllers for their solar electric systems havebattery based systems and the purpose of standard charge controllersare to keep the solar panels from overcharging the batteries (which canpermanently damage batteries).
A charge controller with an LVDfeature, not only keeps the solar panels from being overcharged butalso prevents batteries from becoming over discharged. If the solararray does not provide sufficient charge to offset the daily loadrequirements you are at risk of damaging your battery bank. If morethan 80% of full charge is discharged from lead acid batteries and thebattery is left in a discharged state for weeks or months, thebatteries will be damaged permanently, which will cost you a lot ofmoney to replace.
LVD monitors the state of charge (SOC) andautomatically disconnects the loads from batteries if a certaindischarge threshold has been reached thus protecting your batteriesfrom being over discharged. Typically an alarm system notifies you thatthe battery bank needs attention before the loads are cut off. A chargecontroller with LVD gives you both overcharging and over dischargingprotection in one single unit.