Historically the most popular selling housing style for an inductive proximity sensor has been the tubular style. The more popular sizes tend to be M8, M12, M18 and M30. Smaller tubular sizes of 3 mm, 4 mm, M5, and 6.5 mm are also available and have seen increased sales in the most recent years. One issue that may affect a tubular sensor’s application is its length. Most standard models are 50 mm to 65 mm long while some shorter body types may be in the 30mm range. What if your application requires 1.5 to 3 mm of sensing range, but you only have 10mm of depth to allow for the sensor? Try looking at a block or rectangular style inductive proximity sensor.
Miniature block or rectangular style inductive proximity sensors are great for shallow depth applications due to the location of their sensing face. Most tubular sensors have their sensing face at the end of the tube in line with the body of the sensor. That means the full length of the sensor (50mm for example) must be accommodated behind the sensor target in order for the sensor to fit. The advantage a miniature rectangular style provides is that its sensing face is located at 90 degrees compared to the length of the sensor. This means only the depth of the sensor must be taken into consideration rather than the length of the sensor for space critical areas. For example, on a 5x5x25 mm sensor, the sensing face is located one of the 5mm depth surfaces.
Miniature rectangular inductive sensor sizes are available from a 5x5x25 mm size up to an 8x20x32 mm (HxWxL). The 5×5 size can provide sensing ranges up to 1.5 mm which is equivalent to a standard M8 tubular sensor. The very popular 8x20x32 mm size can provide sensing distances up to 7 or 8mm which is equivalent to or better than many M18 tubular size models. Other popular rectangular housing styles such as 8x8x40 mm, 4x8x16 mm, and 6x10x30 mm are also available with sensing ranges from 1.5 mm to 3 mm.
If your next application requires the need for your inductive proximity sensor to be less than 10 mm “long” don’t forget the advantages a miniature rectangular style sensor can provide. In many applications these provide the sensing range desired in a housing depth that is required.