There is a certain problem in our equipment that needs to be grounded to ground the negative pole of the 12V DC switching power supply. This DC switching power supply is the total power supply of weak current in the equipment. What I want to ask is whether such a solution is possible. Are there any hidden dangers?
Sheldon 发表于 July 14, 2020
Under normal circumstances, there is no problem, but in fact, your 12V is derived from 220V, but the 12V power supply is independent of the 220V power supply. The 220V ground wire is commonly known as the earth, in order to play the role of shielding and leakage protection. If the two ground wires are connected together, when the 220V leaks, 220V electricity will pass through the ground wire. Because the electric potential difference of 12V is superimposed on 220V, the 12V which is originally a safe voltage may cause electric shock, resulting in accidents occur.
Roderick 发表于 July 14, 2020
Are you directly connected for electromagnetic compatibility, choose resistance-capacitance grounding, and generally choose floating ground for DC grounding. In different power supply systems, if leakage occurs, the shell is grounded, and the ground level is no longer zero potential. Whether the low-voltage distribution system is TN-C or TN-S protective ground is different when the leakage occurs.
Leanne 发表于 July 14, 2020
Does the DC power of this switching power supply have to be grounded? I have only heard of AC grounding, but not DC grounding. DC grounding always feels wrong. . .
