Press the button or inset the USB load, USB output function works and the LED lights will indicate the capacity. If have no load the LED will turn off about 3 seconds later, And the USB out will turn off 120 seconds later. To repeat the procedure by pressing the button again If over-current, short circuit protection and so on, remove the USB cable, reinsert or push the button before open the output.
AC OUT Function
Toggle switch up to the ON, AC output open, down to the OFF, AC output turn off if over-current, short circuit, over voltage, under voltage, over temperature protection, must reset the switch first to ON then AC output open.