Proximity Switches

An inductive proximity switch works with a high frequency oscillating circuit that creates an alternating electromagnetic field on the active sensor surface by means of a coil. When a metallic object nears this field a damping occurs in the oscillating circuit. If this damping exceeds a threshold value, a switching signal is generated.

Basically they detect metal - in general the bigger the inductive proximity switch the longer the range. We have a range of suppliers and many different options - the easiest way to find the best product is to email powelectrics with your requirements and we will put forward what we consider to be most appropriate.

A capacitive proximity switch works with a high frequency oscillating circuit that creates an electromagnetic field on the active sensor surface by means of a capacitor. When a substantial or fluid substance nears this field a capacitance unbalance occurs and leads to a variation of the amplification in the oscillating circuit. If this amplification exceeds a threshold value, a switching signal is generated.

We are able to offer a wide range of capacitive proximity switches from a number of manufacturers. Please email us your enquiries and we will offer the most suitable switch for your application.

Ultrasonic sensors use the time of flight measurement principle of ultrasonic pulses in order to accurately and repeatably determine the position and distances of objects in automatic processes.

Specially coded ultrasonic signals are transmitted in a set pattern and then reflected by the target object. This reflected signal is then received by the sensor and decoded. The recorded time of flight is temperature compensated and converted to distance.

Ultrasonic sensors are used for many different tasks, including:

• Detection of moving objects, including glass
• Presence detection of objects and people
• Object counting
• Completeness checks
• Level measurement
• Winding and unwinding control of coils of paper, textiles and foil
• Web tension or loop control
• Collission avoidance

Photoelectrics proximity switches, whether they be diffuse, retro-reflective or through-beam, incorporate a light emitter and a receiver. In all but through beam types, the emitter and receiver are housed in a single sensor unit.

Typical Applications for photoelectric proximity switches include:

• Counting and monitoring over longer distances e.g. conveyor, packaging and handling systems.
• Bottling and canning plants.
• Food making.
• Sorting by height detection.
• Controlling doors, gates and corridors.
• WITH FIBRES ; Counting, checking and sorting of small objects.
• Controlling and monitoring assembly operations, In areas with low/high temperatures or in the vicinity of very strong electromagnetic fields.