In view of the current situation of the lack of electricity loads in LVDC system, the power supply principle of some conventional loads is analyzed, the DC power supply test or transformation of such loads is realized to meet the application requirements of the system on this basis. In addition, the arc problem of load application in LVDC system is analyzed, and an arc-free plug-in method of DC loads based on capacitors and semiconductor switches is proposed, of which he load and capacitor are connected in parallel and then connected in series with the semiconductor switch. Through the arc extinguishing characteristics of the semiconductor switch and capacitor, arc free disconnection can be realized. The test results show the effectiveness of the above method.