Sensors to Measure Proximity

Digital Proximity Switches for Detecting Steel

To detect when a piece of steel is within a specific proximity of a sensor we offer Ferrous Metal Proximity Sensors. Our 275VPD sensors detect a steel plate at 0.4” or closer. These sensors can be custom programmed for turning on/off at specific gaps to the specific target being detected. Our larger Ferrous Metal Proximity Sensors are capable of detecting steel targets at larger gaps and contain potentiometers that allow for field adjustment of the switch point in the application.

Digital Proximity Switches for Detecting Magnets

When proximity detection is required of non-steel targets, it can be measured by attaching a magnet to the target.

• Single Channel Hall Switches switch on when a magnetic field of the proper pole is near the sensor. Dual Output Hall Switches provide an output for each magnetic pole allowing for detection of proximity of two different targets from a single sensor by mounting 1 magnet with the North Pole Out and 1 with the South Pole out.
• Coded Alignment Sensing Systems are tamper-proof Proximity Sensors for uses in applications where the end user may try and fool the system that the target is in position using a different magnet.

Analog Position Sensors for Detecting Steel

Ferrous Metal Position Sensors provide an analog output that increases as steel approaches or passes by the sensor face. 275VPA sensors are standard programmed to detect a large steel target over approximately 3/8” of travel. Larger analog ferrous metal position sensors are able to detect steel targets at gaps up to 3.5”.

Analog Position Sensors for Detecting Magnets

Analog Hall Sensors provide an analog output that increases or decreases as the magnetic field changes. Dependent on the sensitivity of the sensor and the size of the magnet these sensors can be used to track proximity over a variety of gap ranges.

When using magnets and Hall Effect Switches or Analog Hall Sensors the size shape, and material of the magnet will determine the output state at a given gap. This Application Note provides charts showing operate gap ranges for Hall Effect switches and also detail magnetic field strengths that can be used to calculate analog sensor voltages. Magnets can also be detected through non-ferrous target such as aluminum or plastic cases.

Target magnets for proximity measurement are available with the South Pole Marked for use with our sensors. Magnets are also available mounted into bolts and other threaded targets for easy installation or built into two piece clamping collars for mounting direct to rotating shafts.

If you do not find the proximity sensor you need in our catalog, contact our Engineers to discuss a custom solution.