In metalworking applications.

In metalworking applications, proximity switches generally fail to be paid to mechanical damage caused when the intended target physically contacts the switch or because coolant attacks plastic materials and penetrates seals. Fortunately, although new efector in proximity switches from ifm efector inc., Exton, Pa., get the better of both of these problems.
In order to shape damage from physical contact, many manufacturers propose "rugged-duty" switches in all-metallic housings, including the sensing face.

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