The 803-A64X Rotating Cam Limit Switch by Allen-Bradley is a Style A heavy-duty circuit control device with double shaft extension modification and with a NEMA 4 and 13 enclosure used for the control of long-lived, heavy-duty machinery with dedicated cycle operations, in an industrial process when machine motion correlates with shaft rotation. It has a moving switch, which can move in either position on any plane, and it provides contact actuation as the shaft rotates. It comes with 6 cam-opened N.C. contact circuits, a spring-loaded cam-roller, and 6 cam assemblies with user-adjustable segments. The 803-A64X also has a rotating shaft, with 150 RPM of maximum shaft speed. There is a slot in the shaft (keyway) for connecting machines to the moving shaft. Contact actuation is achieved through the brushing of the cam lobe (upper cam segment) on the cam-roller, and the 25A N.C. contact with 150/15A MAKE/BREAK AC ratings at 120 Volts AC is opened, and when the valley passes through the cam-roller, the circuit is deactivated.

The 803-A64X has a cam activation timing measured in degree angles which are determined by the position of the cam segment on the shaft relative to the keyway position, and the 803-A64X, like every Style A device, has a minimum and maximum cam duration of 14 and 346 degrees, respectively. It has an activation period (dwell time) determined by the size of the upper cam segment, and the maximum dwell time is achieved in the device when all 6 cam lobes are off-set to the maximum angle, and a minimum dwell is achieved when all cam lobes aligned. The device has internal dwell time and Cam timing adjustment, and setting of the device timing and dwell time provides circuit control. Its functional temperature range is -30 to 66 degrees Celsius (-22 to 150 degrees Fahrenheit), with a storage range of -30 to 93 degrees Celsius (-22 to 200 degrees Fahrenheit), and it fits in a NEMA Type 4, and 13 rated enclosure. It weighs approximately 14.1 kilograms (31 pounds), with shipping dimensions of 211.1 millimeters x 144.5 millimeters x 200 millimeters (8.31 inches x 5.69 inches x 7.88 inches), and it has CE, UL, and CSA-certification.