2022-09-26
What are the factors that cause the conductivity of the three-proof paint?
1. The cleanliness of the PCB board
There is dust and moisture on the surface of the PCB board, which makes these substances become conductors. When using the equipment to test, the displayed current data is abnormal. For such problems, as long as the PCB board is cleaned and glued, it can be completely cured and tested again. get conclusion.
2. Test Node
The test node refers to the monitoring node set by the factory during the production process. Some factories set the test node to test the PCB board after baking it for about 1-2 hours. Therefore, some PCB boards may not be fully cured after the furnace. Test at this time, the resistivity of the conformal paint has not reached the optimum state, resulting in abnormal test current. As long as the abnormal test board is tested again, the result can be verified. It is recommended to delay the test node, or extend the heating and curing time.
3. Curing strength
The curing strength of conformal paint can be characterized by hardness, adhesion and so on. For example, after the conformal paint is cured, the hardness has not yet reached the technical requirements, indicating that the curing strength of the conformal paint at this time is not complete, and the electrical properties at this time have not reached the best insulation state. If the PCB board is conductive, the surface hardness of the three-proof paint can be checked and judged. If the hardness is not up to the standard, there may be a phenomenon of decreased insulation.
There is dust and moisture on the surface of the PCB board, which makes these substances become conductors. When using the equipment to test, the displayed current data is abnormal. For such problems, as long as the PCB board is cleaned and glued, it can be completely cured and tested again. get conclusion.
2. Test Node
The test node refers to the monitoring node set by the factory during the production process. Some factories set the test node to test the PCB board after baking it for about 1-2 hours. Therefore, some PCB boards may not be fully cured after the furnace. Test at this time, the resistivity of the conformal paint has not reached the optimum state, resulting in abnormal test current. As long as the abnormal test board is tested again, the result can be verified. It is recommended to delay the test node, or extend the heating and curing time.
3. Curing strength
The curing strength of conformal paint can be characterized by hardness, adhesion and so on. For example, after the conformal paint is cured, the hardness has not yet reached the technical requirements, indicating that the curing strength of the conformal paint at this time is not complete, and the electrical properties at this time have not reached the best insulation state. If the PCB board is conductive, the surface hardness of the three-proof paint can be checked and judged. If the hardness is not up to the standard, there may be a phenomenon of decreased insulation.
