When industrial computers are designing EMC, the first consideration is the EMI (electromagnetic interference) design of the board itself. At the same time, the use environment of industrial computers is relatively complex. In addition to considering the electromagnetic radiation interference of industrial computers, preventing external factors from causing interference to industrial computers is also an important point of EMC design. That is, the EMC design of industrial computers is bidirectional.
1. EMC design of industrial computer cooling port
A better way to deal with electromagnetic radiation, both internally and externally, is to shield the electromagnetic radiator with a hermetically sealed metal box. Due to the factors of heat dissipation and external expansion equipment, industrial computers cannot be strictly sealed. A well-balanced design between heat dissipation and electromagnetic leakage is required. Experiments show that the square heat dissipation port has a better effect on preventing electromagnetic leakage than the circular heat dissipation port.
2. EMC design at the joints of the chassis
According to theory, when the distance between two contact points on the industrial computer case is greater than a certain value, electromagnetic radiation may leak between the two points. Therefore, the design of the chassis seam is also an important indicator to verify the EMC design.
The material used in the industrial computer case is high-quality aluminum alloy, which has its own anti-deformation properties, and the industrial computer case is mostly horizontal.
In addition, the seam between the board and the chassis is also a place that is extremely prone to electromagnetic leakage. Multiple boards will be inserted into the industrial computer. The tight contact between the board and the chassis is an important indicator of electromagnetic compatibility. Therefore, the industrial computer with excellent workmanship will use EMI shrapnel to ensure that the seam between the board and the chassis is tight and reliable. .
3. The special design of the chassis surface
First of all, when the industrial computer is used in a strongly corrosive environment, such as at sea, the inner and outer surfaces of the chassis must be treated with anti-corrosion treatment.
Secondly, in the vibration environment of the industrial computer, some electrical components in the chassis will come into contact with the inner surface of the chassis, and the industrial computer is required to be painted inside to make the inner wall of the chassis non-conductive, so as to avoid short circuits and burn the equipment.
