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Ever feel like your proximity application isn’t working just right? Maybe it’s the inductive sensor selection.

Understanding the following three inductive mounting principles is key to selecting the ideal sensor for your application and/or figuring out why the one you have isn’t working correctly. So which inductive is best for your application?


Flush (shielded) sensor

Typically having the shortest sensing range, a flush (shielded) sensor has a sensing field that will only sense objects that approach it from the face of the sensor. The entire face of the sensor can be surrounded by metal and the sensor face sits flush with the mounting surface. It is designed specifically to send the sensing field out the front of the sensor. We see this a lot in metal stamping dies because the flush mounting protects the sensor from the often-destructive atmosphere of the press.


Non-Flush (non-shielded) sensor

A non-flush (non-shielded) sensor has a sensing field that comes out the side of the front of the sensor, allowing it to sense objects from the side and giving it a greater or longer sensing range. But you can’t have metal around the face of the sensor. Otherwise it might accidentally detect the environment rather than a specific target.


Factor 1 or multi-metal sensor

A Factor 1 or multi-metal sensor adjusts the sensing range for all types of metals, most importantly those that are not steel. An inductive sensor has a correction factor. Based upon the type of metal, the sensing range is reduced. They are specially designed to trigger for most any metal target at the same sensing distance. This is important as many hybrid/electric automotive and consumer goods applications are using more aluminum and custom metals today.


More to consider

When choosing an inductive sensor, think about what you’re trying to detect. For example, if it’s not steel or is iron-based, a factor 1 or a multi-metal inductive sensor that is a special inductive technology will allow you to see all metals, basically at the same distance.

Traditional inductive proxes are designed for steel/ferrous targets. When presented with a metal like aluminum or copper there is a correction factor to reduce the sensing distance. This can cause problems in sensing applications.

Virtually every inductive proximity sensor vendor offers these three modes to allow for adaption to your specific application and target.

Each metal that you’re trying to detect has a different correction factor for an inductive sensor. So if you’re working with aluminum, for example, you’ll want to look for something that has Factor 1 or multi-metal sensing. If you’re trying to detect copper, Factor 1 has the most value.

Many industries – traditional automotive and electric vehicles, appliance, metalworking, forming, bending and even food and beverage industries – rely on inductive sensors in their automation applications. They sense objects without any physical contact with the target or the object being sensed.

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Balluff is one of the world’s leading sensor manufacturers, providing innovative and practical sensing solutions for a wide range of applications and industries. With more than 90 years of experience and 68 locations around the globe, Balluff specializes in delivering dependable, rugged products for industrial sensing, networking, and industrial identification to help prevent downtime, eliminate errors, and innovate the way their customers automate. For more information, visit: