The 803-A3 Rotating Cam Limit Switch by Allen-Bradley is a 3-circuit control device, used with heavy-duty machinery with a repetitive operation where the machine motion directly correlates with the shaft motion. The device, like most Bulletin 803 Devices, is made for long-life and heavy-duty operation, and it has a switch which can rotate in any direction on any plane. The 803-A3 comes with 3 independent cam operators, a rotating shaft, a spring-loaded cam-roller, and an adjustable cam segment with both higher (lobe) and lower (valley) segments. It has a 25A normally-closed contact with both AC and DC ratings, and it has 150A/15A and 30/3A MAKE/BREAK current ratings at 120 Volts AC and 600 Volts AC, respectively. The 803-A3 has a slot in the shaft (keyway), which connects the driven shaft to machines, and its circuit is activated when the lobe makes contact with the cam roller, and it is deactivated when the cam valley passes through the cam roller. The device has a timing (with activation by the cam) determined by the position of the cam on the rotating shaft with reference to the Top Dead Center (TDC), and it has an activation duration (Dwell Time) determined by the size of the cam lobe, and the position of the cam segment. The 803-A3 has a rotating shaft with a 150 RPM maximum shaft speed, with a cam duration range of 14 degrees to 346 degrees, and it comes with a regular left-hand shaft extension. It has a working temperature range of -22 to 150 degrees Fahrenheit, with a NEMA Type 1 rated enclosure, and it can be stored at a -22 to 200 degrees Fahrenheit temperature range. The 803-A3 has overall shipping dimensions of 4.38 inches x 5.69 inches x 7.88 inches, with an approximate weight of 9.5 pounds, and it is CSA, UL, and CE-certified.