The Allen Bradley 803-E4 is a cam limit switch that belongs to the 803 family of rotary limit devices. This switch is used to control the rotation of machines in industries and is generally used for applications in packaging, steel manufacturing, motor control, electrical appliances, and many other industries. The 803-E4 can limit switch can easily detect the position, speed, and range of motion of a rotating machine and consumer appliance. The rotating shaft of the switch is attached to the machine to be controlled and the switch is automatically activated when the shaft reaches a set number of revolutions. The 803-E4 switch comes in a Type 13 enclosure and has a 25 A N.C. double break contact; this device features between 2 and 12 independent cam operators and it can be operated to a maximum limit of 150 RPM shaft speed. The user can set the cam duration between a minimum of 15 degrees and a maximum of 360 degrees. The 803-E4 cam limit switch actuates contacts by using its cams, which are mounted on a rotating shaft.  A cam can be adjusted easily without affecting other circuits; the 803-E4 opens and closes the contacts at various angles of rotation of a machine shaft.

This device is equipped with precision bearings for smoother rotation of switch shaft assemblies. This switch can be mounted at any angle or in any plane with the help of screws. The Allen Bradley 803-E4 cam limit device is easy to operate and requires next to no maintenance. It is designed for heavy-duty continuous operations in industries.