What are the key protection strategies for EMC immunity design of infusion pumps according to the IEC60601-1-2 standard?

The design must adopt zoned protection strategies tailored to different types of interference. For electrostatic discharge, the focus is on all user-accessible metal parts and interface ports. It is essential to provide low-impedance discharge paths from these points to the chassis or protective earth, supplemented by TVS devices for clamping. For electrical fast transient bursts, whose energy is primarily coupled through power lines and signal lines, the key design approach is to use a combination of integrated filters and TVS devices at the power entry point, and to implement common-mode filter circuits or shielded cables for sensitive long signal lines. For surge impacts, the main threats come from AC power lines and long-distance communication lines. It is necessary to deploy high-current-capacity varistors or surge-grade TVS tubes at the power input, and to use optocouplers or magnetic couplers with secondary protection circuits for isolated communication interfaces. The foundation for all these strategies is a well-defined PCB grounding partition and a complete metal shielding enclosure.