How to suppress power line overvoltage in a power line carrier PLC?

Suppressing power line overvoltage in power line carrier PLCs requires the deployment of overvoltage protection devices. A 14D511K varistor with a clamping voltage of 510V and a response time ≤25ns is used at the power line inlet. This is paired with a 2R600L-8×6 gas discharge tube to handle high-energy overvoltages. An SMCJ24CA TVS diode with a clamping voltage of 38.9V is used in the secondary circuit. The design conforms to IEC61000-4-5 standard, with test waveforms ranging from 1.2/50μs to 8/20μs. In actual testing, the system should be able to withstand surge impacts of ±4kV. Suppressing overvoltages protects internal circuitry and extends equipment lifespan.