The 803-A3RH is an 803 series type Rotating Cam Limit Switch, manufactured by Allen-Bradley. It is a control circuit device that can sense a certain number of conditions, and is used with mechanisms that make a repetitive cycle of operation in which the actual motion is linked to the shaft rotation. The 803-A3RH rotating cam limit switch is designed to open and close control circuit contacts at user-defined angular positions of mechanisms. This is done by a rotating motion in both directions when the device is mounted in any plane. It is mechanically constructed for a heavy duty operation with a huge number of executed operating cycles.

The Allen-Bradley 803-A3RH limit switch contains a total of three different switching circuits, which are basically three separate cam-roller assemblies that are all mounted to the contact base. The current rating for these switching circuits (double break contacts) is 25A with an enclosure type of 1. When looking from the face side of the device, its shaft extension stretches out to the right. The 803-A3RH, like all bulletin 803 limit switches, consists of the following main parts: a conduit entrance each side, 25 Ampere cam opened contacts (normally closed), adjustable cam segments with vibration resistant locking nuts, a 3/4” shaft, rugged cast iron side plates, and a heavy-duty steel base. For the purpose of timing and dwell adjustments, the user must remove the cover and internally set up mechanical settings. The product’s dimensions are 7.88 x 5.69 x 6.64 inches (200.1 x 144.5 x 168.7 millimeters) and its shipping weight is approximately 21 pounds (9.5 kilograms). Its operating temperature range is around -22 to 150 degrees Fahrenheit (-30 to 66 degrees Celsius). This product was discontinued in 2007.