How to pass the ESD electrostatic discharge test for frequency inverters

To ensure inverters pass ESD electrostatic discharge testing, a comprehensive protection system from the enclosure to the ports is required. ESD primarily couples into the system through metal parts, gaps, and interfaces accessible to operators. Protective measures include: the metal enclosure must be reliably grounded to provide a low-impedance discharge path for ESD current. Plastic enclosures must ensure sufficient air gaps and creepage distances between internal circuitry and accessible surfaces, or an internal grounded metal shielding layer should be added. Transient voltage suppression devices should be placed on signal and power lines at all I/O ports (such as control terminals and communication ports). For low-speed digital and analog ports, general-purpose ESD protection diodes, such as ESD5V0D3B, can be used; for high-speed communication ports, low-capacitance TVS/ESD arrays, such as the ESD SRVLC series, should be selected. Protection devices should be placed as close as possible to the interface connectors. On the PCB, the interface area should be separated from other circuits by ground planes or trenches. RC filters can be added for critical control signals such as reset and enable. On the software side, watchdog timers and state recovery mechanisms should be added. During testing, focus on inspecting metal parts, gaps, buttons, and interfaces for contact discharge and air discharge points. By adopting the multi-layer protection scheme of Yinte Electronics, the frequency converter can robustly pass ESD tests of ±8kV or even higher levels.