Inductive Proximity Sensors
In: Available in many shapes and sizes, but all use wire winding around a ferrite core which emits a RF field from the sensing face. When metal targets approach the RF field they are detected without actual contact. Commonly applied at a range of 1mm (0.039") to 60mm (2.36").

Capacitive Proximity Sensors
Ca: Come in many shapes and sizes, but all contain a metal plate in the sensing face. Targets often include liquids, granular materials, paper, glass and wood. The target and metal plate work together to create a capacitor and as a target moves closer, the capacitance changes until an output is generated. Effective at ranges from 1mm (0.039") to 50mm (1.96").

Photoelectric Proximity Sensors
Ph: Offered in a wide variety of sensing modes and physical configurations, but all use some form of light energy to detect targets. Target materials are quite extensive and selection depends on the target's reflective properties. Models are available with sensing ranges from 1mm (0.039") up to 20 meters (65 feet).

Ultrasonic Proximity Sensors
Us: Devices that use high frequency sound waves to detect the presence of an object. Good target materials are solids, liquids and granular media due to their high reflectivity and unlike photoelectric sensor, target color and dusty environments do not effect them. Commonly applied in applications from 60mm (2.36") to 8.0 meters (26 feet).

Machine Vision & Smart Sensors
Mv: The application of computer vision to industry and manufacturing. Machine vision works with other digital input/output devices on a computer network to control manufacturing equipment such as robotic arms. Commonly applied in applications from 60mm (2.36") to 3.0 meters (9 feet).

Rotary Encoders
Er: Sometimes called a "shaft encoder", they are electro-mechanical devices which sense the angular position, motion, of a shaft or axle and convert it into an analog or digital code. Two main types; "absolute" encoders indicate current shaft position, "incremental" types provide shaft information that's further processed into speed, distance, and position.

Limit Switches
Ls: Switches that operate just like an ON/OFF switch, but they are equipped with specialized rollers, levers, etc. When actuated the limit switch outputs a control signal(s). Unlike proximity sensors, limit switches must be physically contacted to operate.

Safety Switches
Ss: Mechanical types and non-contact types. Some safety switches have a two-part switch consisting of a 1) switch body and 2) a unique operator or "key". In order to generate an output signal(s) the unique key must engage with the switch body. Used in machinery to protect workers from unsafe access to machine areas.

LVDT, Probes & Transducers
Tr: All provides very accurate positional feedback as a plunger physically contacts and moves against a target or work piece for measuring and gauging purposes. Newer models use a movable target that traces a path along a rail, and the movement creates a variable output equal to the travel.

Thermocouples & Probes
Tc: Commonly a probe-shaped device containing two dissimilar metal wires, which are used to measure temperature.

Pressure Sensors & Switches
Ps: These are attached to pipes and vessels to monitor this critical condition within a process or system.