... and reverse connection of polarities protection.LCD backlight, digital keyboard and knob.High resolution.8 groups setting ... groups, 32 steps each groupBattery testing0.01mAH~4000AHInterfaceRS232, RS485, USB(option)ProtectionOver-voltage, over-current, over-power, ... cable, handle bars, software CDOption accessoriesRS232 adapter, RS485 adapter, USB adapter, Mounting rackPower source115V/230VAC±15%, 47~ ...