Product Description:

The EA170-51100 is a rotary limit switch manufactured by Danaher for the Snaplock Limit Switches series. Installed on cam-driven shafts, it converts angular position into isolated electrical signals so controllers can stop or reverse motion in automated equipment once a preset angle is reached. The device acts as a mechanical feedback element that withstands repetitive cycling in conveyors, valve actuators, and indexing tables where precise travel limits are required.

This model employs a double-break mechanism, separating each circuit at two points to improve arc suppression. Its contact block is wired in a 2NO/2NC configuration that provides two normally open and two normally closed outputs. Switching capacity reaches 20 A at 125 VAC, allowing direct control of motor starters or solenoid valves. The die-cast enclosure carries a NEMA 1, 4, and 13 rating, protecting the internal components from dust, splashed water, and cutting fluids. Lever orientation can be indexed in 7°30′ steps throughout the full 360° range to match cam placement, and the mechanism trips after 10° of rotation. The contacts maintain electrical isolation between the two controlled circuits during operation.

The actuator has 13° of recommended overtravel and 8° of reset travel, while total permissible shaft movement reaches 37° before the mechanical stops engage. A reverse shaft orientation allows mounting on the non-drive side of a cam, and the sensing arm is calibrated for clockwise operation. Contact geometry follows the Form Z pattern, and the switching elements have silver alloy contacts to reduce electrical resistance over repeated cycles. Actuation requires 30 lb-in of torque, which can be supplied by typical cam followers. The wide mounting pattern provides secure installation on panels exposed to vibration. These operating characteristics allow the switch to respond consistently when a rotating shaft reaches its preset travel position.