It sounds like you're referring to different types of sensors commonly used in industrial automation and control systems. Let's break down each term: Sensor Type (PNP-NPN): PNP (Positive-Negative-Positive) and NPN (Negative-Positive-Negative) are transistor output configurations used in sensors. These terms indicate the type of transistor used for the output stage of the sensor. PNP sensors source current from the positive supply voltage, while NPN sensors sink current to the negative (ground) supply voltage. Proximity Sensor: Proximity sensors detect the presence or absence of objects without physical contact. They work by emitting an electromagnetic field (inductive proximity sensors) or infrared light (photoelectric proximity sensors) and detecting changes caused by nearby objects. Photoelectric Sensor: Photoelectric sensors use light beams (usually infrared) to detect the presence, absence, or distance of objects. They can be used for various applications like object detection, counting, or sorting based on light reflections.

Eye-Mark Sensor: Eye-mark sensors are specialized photoelectric sensors used for detecting specific marks (eye-marks) on products or materials. These marks are typically printed or applied for precise positioning or identification in manufacturing processes. Capacitive Sensor: Capacitive sensors detect changes in capacitance when an object enters the sensor's detection field. They are used for detecting materials, level sensing (liquids or solids), or proximity detection in certain environments. Inductive Sensor: Inductive sensors detect metallic objects based on changes in inductance. They generate an electromagnetic field and detect changes in the field caused by the presence of conductive materials. These sensor types are essential in industrial automation for tasks such as part detection, positioning, sorting, and quality control. Each type has specific advantages and is chosen based on factors. Like the type of material being detected, environmental conditions, and the required accuracy of detection. The choice between PNP and NPN sensors depends. The specific application and the compatibility with the control system being used. Sensor | Delta | Siemens | Omron | Sick | Truck | Fatek | FOTEK | Kongsberg |