Precautions:1. The power supply circuit on the main board has no fuse, and the built-in self-addition cause permanent damage to the chip on the board (even 2 seconds is not allowed). 2. During normal operation, there is sampling overcurrent protection at the motor output. Since the module power and current are very large, please do not short circuit when the module is not working normally. Once the short circuit has the possibility of burning , the first wiring test machine Please use small current and low voltage test, after ok, then pass high current and high voltage, because it is bare board module for sale, pay attention to the wiring line insulation, strong voltage is not allowed to the board parts. 3. Do not connect the motor that is obviously inconsistent with the voltage and current of module or is far away from the motor to avoid inexplicable damage. 1.MA MB phase line output connection motor 2. 5V GND motherboard comes with 5V power supply (current does not exceed 30MA)