Siemens 3TF20-10OBF4 Industrial AC Contactor

Siemens 3TF20-10OBF4 is a three-pole World Series contactor designed for reliable AC-3 motor switching in industrial control panels. It features a 110 V DC coil and includes a single normally open auxiliary contact (type 10E) for control signaling, with screw terminals for straightforward wiring. In the 3TF20 family, this configuration is rated for up to 4 kW at 400 V, making it suitable for common motor tasks such as pumps, fans, conveyors, and machine tools in industrial applications. The compact design integrates with standard Siemens motor-control configurations and supports accessories within the 3TF product line for standard panel mounting and interlocking needs. This model represents Siemens’ long-standing approach to modular motor starters, providing a proven core solution for initiating and stopping three-phase motors in automation projects.