How to shield the gaps in the HMI panel?

Addressing electromagnetic leakage from HMI panel gaps is crucial for improving overall shielding effectiveness. Panel gaps primarily exist between the front panel and the casing, and at mounting openings for various components. For the joint between the front panel and the casing, conductive gaskets should be used, such as beryllium copper finger springs, conductive rubber, or metal mesh gaskets. Sufficient compression and contact pressure must be ensured during installation to create a low-resistance conductive connection. For button and knob openings, plastic parts with a metallic coating should be used, or a metal spring should be added inside a non-conductive plastic button to connect it to the internal circuit board ground when pressed.

Indicator light openings can use lamp holders with metal rings, or the LEDs themselves can be shielded with a metal cover. The display window is the largest gap and must be shielded, such as glass or plastic with a transparent conductive film. The conductive layer around its perimeter must be connected to the panel's metal frame 360 degrees using conductive tape or springs. All screw holes should be free of paint, ensuring direct metal-to-metal contact after screws are tightened. For unavoidable long, narrow gaps, their length should be much smaller than half the wavelength of the highest frequency requiring shielding; otherwise, a short-circuit point must be added in the middle. Through careful design and the use of Echotech's professional conductive shielding materials, electromagnetic leakage from panel gaps can be effectively minimized.