How does a scr conduct?

A silicon-controlled rectifier (SCR) conducts when a small gate current is applied, allowing it to switch from a non-conducting to a conducting state. Once triggered, the SCR remains in the conducting state even if the gate current is removed, as long as the anode-to-cathode voltage remains above a certain threshold. It continues to conduct until the current through it falls below a critical level, known as the holding current, allowing it to turn off. This property makes SCRs useful in applications like power control and rectification.