The 803-P4LHW is a Rotating Cam Limit Switch from the family of 803 switches manufactured by Allen-Bradley. This robust pilot device is generally used with rotary tables and presses and in the building and machine industry. It enables sequential positioning and control by providing position feedback, and when through a chain drive the movement is detected on the rotating cam limit switch, this device will, according to dwell and timing settings, actuate the control contacts. The user can perform the installation of this device in any plane.

The 803-P4LHW has a “Style P” shaped housing. The switching circuit is divided into four separate circuits (each with an independent cam operator). These switching circuits are normally closed, cam opened, and with a switching capacity of 25A. This rotating cam limit switch is equipped with a type 1 industrial enclosure and its shaft extends from the left-hand side when viewing it from the face side of the device. The device with the 803-P4LHW part number is available with a factory modification (an external adjustment sprocket for a 0.38 inch No. 35 chain) for means of changing the relative position between the shaft and the driving mechanism. The user will bring the device to a standstill, then pull out the knurled knob to unlock the spline. Now the shaft with cams can be turned in steps of 5 degrees. The external adjustment sprocket is the one with 48 teeth with a 5.73-inch pitch diameter. The Allen-Bradley 803-P4LHW part has a shipping weight of 18 pounds (8.2 kilograms). This device operates in the temperature range of -22 to 150 degrees Fahrenheit (-30 to 66 degrees Celsius) and was discontinued in 2007.