803-A9

The Allen-Bradley 803-A9 Rotating Cam Limit Switch is a 9-circuit, heavy-duty control device used with long-life and heavy-duty machinery with dedicated cycle operations for industrial applications where the motion correlates to the switch shaft rotation. The device makes use of a cam mounted on a shaft, with the switch being able to move in either direction on any plane, and the cam provides circuit actuation as the shaft rotates. The 803-A9 is a Style A control device which comes with a 9-cam opened contact circuit (25A NC), a spring-loaded cam roller assembly, a 150 RPM rotating shaft with over-sized ball bearings, and 9-cam assemblies with adjustable lower (valley) and higher (lobe) segments. The circuit is activated as the cam lobe pushes against the cam roller assembly, thereby opening the Normally-Closed (NC) contact, and it is deactivated when the valley passes by the cam roller. Its NC contact has a 25 A carrying current with both AC and DC voltage ratings, and with a real MAKE/BREAK power rating of 1800 VA.

When the circuit activates, the total period of activation is called the dwell time, and it is determined by the size of the lobe, and it has its peak value when the cam lobes offset at the maximum angle, and it has its lowest when all the cam lobes align perfectly. The 803-A9 has a set activation timing, which corresponds to when the cam activates the circuit, and it is determined by the position of the cam with reference to the keyway/TDC, and the device has a timing range (cam duration) of 14 to 346 degrees. Like all Style A series devices, the 803-A9 has internally-adjusted timing and dwell time, and the setting of the timing and the dwell time determines the machine’s control and operations. It has an operating temperature range of -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 comes in an indoor-use, NEMA Type 1 enclosure. The 803-A9 has a default left-hand shaft extension, and weighs approximately 15.9 kilograms (35 pounds), with total dimensions of 12.25 x 5.69 x 7.88 inches.