
Protection against Power Line Carrier (PLCEFT) electrical fast pulses requires multi-stage filtering and isolation. A common-mode inductor CML4532A-510T and a 0.47μF capacitor (X) are deployed at the power input to suppress common-mode pulses. A TVS diode SMCJ24CA is used to absorb differential-mode pulses. Optical isolation, such as TLP281, is used at the signal interface. On the PCB layout, sensitive circuits are kept away from the interface and protected by a ground plane. The protection network is optimized through simulation analysis of EFT pulse propagation. In actual testing, a ±4kV/5kHz pulse test is performed according to the IEC61000-4-4 standard; the system should exhibit no abnormalities. EFT protection can improve system stability in industrial environments and reduce malfunctions.