Siemens 3TX4490-3G Varistor

Siemens 3TX4490-3G is a plug‑on surge suppressor varistor designed for the Siemens 3TX family of contactors. It provides coil‑voltage transient protection by clamping inductive spikes when the contactor operates, helping to extend the life of the coil and surrounding electronics in noisy industrial control environments. The 3G version supports AC coil voltage of 48 V and DC coil voltage in the 24–70 V range, making it suitable for AC 48 V and DC 24–70 V control circuits. It is designed for mounting on contactors with or without auxiliary switch blocks, offering a compact, integrated protection module that can be used with compatible Siemens contactor assemblies. Verified product literature describes it explicitly as a SURGE SUPPRESSOR VARISTOR, intended to safeguard control circuits in industrial automation applications such as panel mounted control and motor start circuits. As part of Siemens’ surge protection lineup, the 3TX4490-3G is employed to suppress spikes across the coil, contributing to reliable operation and protection of downstream control components in applications that rely on Siemens 3TX contactors.