An inductive sensor will detect metals. The change in the inductive field is measured via the metal using a solenoid. Inductive sensors are classified as Type 3 in accordance with ISO 14119.
For example, the safe proximity switch PSENini detects the approach of metallic objects without the use of contacts and supplies the necessary safe signals via positions and end limits. PSENini can also generate the pulse for counting tasks or for detecting rotational movements. Compared with mechanical switches, the inductive sensor provides high productivity and a long service life: non-contact, non-wearing operation, plus high switching frequencies. The safe proximity switch is also insensitive to dust and vibration. When PSENini is connected in series with additional safety switches PSENini and PSENcode, safety gate systems PSENslock and PSENsgate, costs and labour can be reduced because there are fewer safe inputs and less wiring is required.