The heat generated by Mitsubishi inverter is caused by internal losses. In the Mitsubishi inverter, the main part is mainly dominated by the main circuit, accounting for about 98, and the control circuit accounts for 2. In order to ensure the normal and reliable operation of Mitsubishi inverter, we must use the fan to dissipate heat from Mitsubishi inverter. The built-in fan of Mitsubishi inverter can take away the heat dissipation inside the cabinet of Mitsubishi inverter. If the fan does not work normally, it should stop immediately. Mitsubishi inverter runs; high-power Mitsubishi inverter also needs to add fan to the control cabinet. The air duct of the control cabinet should be designed reasonably. All air inlets should be equipped with dust-proof net, and the air is unobstructed to avoid eddy currents in the cabinet. The location forms dust accumulation; according to the ventilation volume of the Mitsubishi Inverter manual to select the matching fan, the fan installation should pay attention to the anti-shock problem.