新买的变频器是工业生产和设备控制中的关键设备，为了确保其正常运行和安全使用，我们在安装和启动之前需要进行一些必要的检查和测试。

以下是一些常见的检查项目： 

1、外观检查：检查变频器外壳是否完好无损，是否有明显的变形或损坏。同时，检查连接线路和接线端子是否紧固可靠。

2、 电气参数检查：检查变频器的额定电压和额定频率是否与电源匹配。同时，检查输入和输出端子的电压、电流和功率是否符合要求。 

3、冷却系统检查：检查变频器的冷却系统，确保冷却风扇和散热器的工作正常。清理散热器上的灰尘和杂物，确保散热效果良好。 

The newly purchased frequency converter is a key equipment in industrial production and equipment control. In order to ensure its normal operation and safe use, we need to conduct some necessary inspections and tests before installation and startup.
Here are some common inspection items:
1. Appearance inspection: Check whether the outer shell of the frequency converter is intact and undamaged, and whether there is any obvious deformation or damage. At the same time, check whether the connecting lines and terminals are securely fastened.
2. Electrical parameter inspection: Check whether the rated voltage and rated frequency of the frequency converter match the power supply. At the same time, check whether the voltage, current, and power of the input and output terminals meet the requirements.
3. Cooling system inspection: Check the cooling system of the frequency converter to ensure that the cooling fan and radiator are working properly. Clean the dust and debris on the radiator to ensure good heat dissipation.