Made up of CPU. Electronic component. Display. Switch power tube etc. In solar power supply system, the action of charge controller is supplying optimal charging current and voltage, charging for battery promptly. High efficiencly, calmly. It can avoid over charging and over discharging and display important value of system, such as charging current. Voltage etc. Temperature correction Full power using Operating temperature ISO9001 attestation Avoid flowing backwards at night High efficiency. Low loss Using life is more than 10 years CE attestation Dread the thurder Quality guarantee 2 years