ABB SNAT Series: SNAT601TAI Module for High-Power Inverter Protection

In a metal rolling mill, the main drive’s ACS 6000 inverter switches 3300V across massive IGBTs at high frequencies to control the rolling stand motor. During each IGBT turn-off, the inherent inductance of the DC bus and connections can cause a destructive voltage spike (overshoot) that exceeds the IGBT’s rated voltage. The ABB SNAT601TAI​ snubber module is installed directly across the DC link terminals of each IGBT or IGBT phase leg. As the IGBT turns off and the voltage starts to spike, the snubber’s capacitor provides a local, low-inductance path to absorb the surge energy, while its resistor dissipates it as heat. This action clamps the voltage to a safe level, directly addressing the core pain point of IGBT overvoltage failure. In this harsh, high-power environment, the SNAT601TAI​ is a frontline defense, preventing catastrophic IGBT shorts that could lead to weeks of unplanned downtime and six-figure repair costs.