Postisolators

Postisolators are a type of electronic component used to prevent or mitigate the effects of unwanted power surges or transient voltages from reaching sensitive electronic equipment. They are typically employed in systems where such disturbances are a concern, such as power grids, telecommunications infrastructure, and industrial control systems. The primary function of a postisolator is to act as a protective barrier, absorbing or diverting excess energy before it can damage downstream circuitry.

These devices operate by utilizing various technologies to manage overvoltage events. Some common mechanisms include Metal Oxide Varistors (MOVs), which exhibit a significant change in resistance based on applied voltage, becoming highly conductive at elevated voltages to shunt excess current. Gas Discharge Tubes (GDTs) are another method, employing a gas-filled gap that ionizes and conducts when a high voltage is applied. Transient Voltage Suppressors (TVS) diodes are semiconductor devices designed for fast response times and precise clamping voltages.

The placement of postisolators is crucial for effective protection. They are typically installed at points where power enters a system or between different stages of electronic equipment that may have varying levels of sensitivity to voltage fluctuations. By strategically deploying postisolators, engineers can significantly enhance the reliability and longevity of their electronic systems, reducing the risk of costly failures and downtime. The selection of a specific postisolator depends on the voltage levels, expected surge currents, response time requirements, and the specific application environment.