uxcell Voltage Converter Regulator DC/DC DC 12V Step-Up to DC 28V 15A 420W Power Boost Transformer Waterproof Waterproof IP68 Voltage Converter Regulator DC 12V to DC 28V 15A 420W. Protections: Over-load, Over-current, Over-temperature, Short-circuit, Over-voltage. Auto-recovery when device is back to normal operating; high transfer efficiency of 95% max.. Die-cast aluminum shell, anti-shock, and moisture-proof and has stronger durability.Widely used in bus, cmb, large trucks, motor, solar generate electricity, display screen of bus and taxi, car audio device Note: It is recommended to use stable DC power for the input power supply If you use the pulsed DC power provided by the generator, please filter it with capacitor before connecting it to the converter. If you use solar panel to supply directly, please note that the open circuit voltage of the solar panel cannot exceed the maximum withstand voltage of the converter. The supply voltage should be within the rated voltage and always leave a certain margin.