The most commonly used are:

• Inductive Proximity Sensors and Switches – It requires a metal target. It produces high frequency altering field at the sensing face. When any metallic material enters in the sensing zone of the switch, the field gets disturbed. A Sensitive detector circuit senses this change which is further processed by amplifier circuit to produce output signal. These are available in senses from 0.6MM to 100MM. The shapes are available in Barrel Round (in AC or DC), Rectangular, Other Special type etc.
• Capacitive Proximity Sensors and Switches – When the object enters in the sensing zone of the switch, capacitance between two plates of capacitor changes. As soon as capacitance value crosses preset level, oscillator starts. This change is detected and resulted in an output signal. It effectively detects non-metallic objects, liquid, powder & granular materials. These Proximity Sensors can also detect materials through glass or plastic walls. These are available in senses from 1MM to 50MM.
• Magnetic Proximity Sensors and Switches – The `reed’ contact of the switch changes when operating magnet passes-by within the sensing range of the switch. The magnetic pickup will generate signal when geared wheel rotates. These switches require a magnet for its operations. These are available as Magnetic Float Switches.
• There are other types of sensors and switches also available with us like the Optical Proximity Switch, Photoelectric Proximity Sensors, LDR types etc.
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