The 803-A8RH Rotating Cam Limit Switch is a Style A heavy duty circuit control device by Allen-Bradley, with Right-Hand Shaft extension modification, and a NEMA Type 1 enclosure, used with industrial machinery with repetitive cycle operation in applications where the shaft rotation equals the machine’s motion. It built for long-lived heavy-duty operations, and it is built for industrial applications like assembly and packing, steel forming, injection molding, and the punch press applications. It comes with a rotating shaft with a 150 RPM base speed, a spring-loaded cam-roller, 8 circuits with cam-opened contacts, and 8 cam assemblies with adjustable cam segments. The 803-A8RH cam has an adjustable lobe (upper segment) which activates the circuits when it pushes against the cam-roller assembly and a valley (lower cam segment) which de-activates the circuit as it passes through the cam-roller.

Its Normally-Closed (N.C.) contact has a continuous carrying current of 25A, with an AC MAKE/BREAK rating of 150A/15A and of 30A/3A at 120 Volts and 600 Volts AC, respectively, and it has a MAKE/BREAK power rating of 1800 Volts A. Its timing is measured in angular degrees, and the timing is a measure of the position of the cam on the shaft, relative to the Top Dead Center (TDC), and it has a dwell time (activation period) determined by the length of the lobe and the position of the cam segment. The setting of the timing and the dwell time provides heavy-duty control, and the 803-A8RH has internal timing and dwell time adjustment. Its total shipping dimensions are 311.2 millimeters x 144.5 millimeters x 200 millimeters (12.25 x 5.69 x 7.88 inches), with an average weight of 16.3 kilograms (36 pounds), and it is CSA, UL, and CE-certified. It has an operating temperature range of -30 to 66 degrees Celsius (-22 to 150 degrees Fahrenheit), in a NEMA Type 1 enclosure, and it can be stored at a -30 to 93 degrees Celsius (-22 to 200 degrees Fahrenheit) temperature range.