Presence sensors

The Allen-Bradley 42JS VisiSight Photoelectric Sensor series features a visible light source for ease of alignment and a rapid 1 ms response time. These presence sensors are suitable for general-purpose detection applications in the packaging, assembly and materials handling industries.

A microchip facilitates advanced diagnostic functions in the sensor which can indicate when unstable sensor operation is occurring. The stability indication provides forewarning against the detection of background noise.

If the signal level is too close to the detection threshold, which can occur due to dust or other interferences, the yellow LED will flash. This provides a rapid and straightforward indication of when maintenance might be needed before both the sensor output and the process itself are adversely affected.

The system also incorporates visual diagnostics for the status of power and output. Multiple LED indicators positioned on the top of the sensor provide rapid visual indication of the current state of the sensor; this simplifies the process of sensor troubleshooting, reducing downtime.

In addition to the stability indication, the ASIC design of the sensor also offers linear sensitivity adjustment and noise immunity. This allows the sensor to address the small form-factor needs in several industries including food and beverage.

The three different sensing modes - diffuse, polarised retroreflective and transmitted beam - cater for sensing ranges between 30 mm to 10 m; sensitivity adjustment is also available with all modes.

An easy-to-install presence sensing solution, the compact 42JS VisiSight is available to suit two popular mounting styles. The rectangular housing with industry standard 25.4 mm hole spacing can be directly mounted, or alternatively an optional snap-on adapter allows the sensor to be used in 18 mm cylindrical mountings.

The sensor enclosures are rated to IP67 or IP40 if the optional snap-on adapter is used. The compact sealed housing and cavity-free design minimises the collection of dust and debris while allowing easy sensor clean-up.