Square D C1707S1T21U Industrial Power Contactor

Square D by Schneider Electric 1707S1T21U is a 120 VAC control coil designed for use with 1707-size (size 2) contactors in D&T configurations. This magnet coil energizes the main contacts to switch heavy loads such as motors, pumps, and conveyors in industrial control panels via a standard 120 V control circuit. The coil is listed for 60 Hz operation, with some catalogs noting a 110 V/50 Hz variant in certain regions. Compatible coil designations for this family include 1707S1T21U and 1707S1T21, ensuring direct interchangeability with the corresponding Square D 1707-size contactor. Typical applications include motor control and general automation tasks in manufacturing and process environments where reliable remote switching of AC loads is required. When used with the appropriate size-2 Square D contactor, the 1707S1T21U coil provides a straightforward, drop-in control solution for 120 V control circuits in industrial panels.