The 803-B84R Style B Rotating Cam Limit Switch by Allen-Bradley is a heavy-duty circuit control switch in the Bulletin 803 heavy-duty control switch series. It is used with industrial machinery with repetitive operational cycles and long-lived industrial operations, where the machine’s motion is determined by shaft rotation. It operates with a shaft-mounted cam that produces contact actuation when the shaft rotates, and it is suitable for applications like packaging, metal forming, injection molding, and punch presses operation. The 803-B84R has 8 heavy-duty control circuits with 10A (1 NC, 1 NO) snap action contact, and 8 independent cam operators with adjustable segments. The switch also has a base rotating shaft that has a 150 RPM maximum shaft speed, and a keyway slot, which connects the machines to the shaft, and it comes with a contact base, spring-loaded cam roller. The 803-B84R is activated when the rotating cam lobe (adjustable higher cam segment) glides through the cam roller assembly, opening contacts 1 and 2 and shutting contacts 3 and 4, and when the cam valley (adjustable lower cam segment) passes by the cam roller, the circuit de-activates.

The duration of activation (dwell time) is determined by the length of the adjustable cam lobe, and the duration is at its maximum when the cam lobes offset at the maximum angle, and it is at its minimum when they align. The cam switch has a timing measured in the degree that determines when the rotating cam activates the circuit, and like all style B series device with timing range of 14 to 346, its timing is determined by the position of the cam with respect to the keyway’s position. The 803-B84R has internal adjustments for both timing and dwell time, which determines machine’s operation, and it comes with an internal speed reducer modification, with factory designated 20 to 1 (20:1) Gear Ratio. It has a standard left shaft extension, and a NEMA Type 4, and Type 13 rated enclosure, and it is built to operate at a temperature of -30 66 degrees Celsius (-22 to 150 degrees Fahrenheit), without impeding contact operation. The 803-B84R weighs approximately 24.9 kilograms (55 pounds), with net dimensions of 311.2 x 144.5 x 200 millimeters (12.25 x 5.69 x 7.88 inches), and it has CE, CSA, and UL certifications.