The **M2PP-91N-R2/N** is a specific electronic component, typically categorized as a **Solid State Pressure Switch** or **Digital Pressure Sensor**, often associated with industrial automation brands like **Norgren** or **CKD**. Below is a detailed breakdown of its technical specifications and electronic components. --- ### 1. General Technical Specifications This device is designed to monitor air or gas pressure and provide a digital/electrical output once a certain threshold is reached. | Feature | Specification (Typical) | | :--- | :--- | | **Pressure Range** | -0.1 to 1.0 MPa (Standard for R2 models) | | **Input Voltage** | 12 to 24V DC | | **Output Type** | 2 NPN Open Collector Outputs | | **Display** | 3½ Digit, 2-color LCD (Red/Green) | | **Connection** | M8 4-pin connector or Lead wire | | **Fluid Media** | Filtered compressed air, non-corrosive gases | --- ### 2. Key Electronic Components & Internal Architecture The unit functions through a combination of sensing elements and signal processing circuitry: #### A. Piezoresistive Silicon Sensor The heart of the unit is a silicon-based micro-machined sensor. When pressure is applied, the silicon diaphragm deforms, changing its electrical resistance. This change is proportional to the pressure. #### B. Analog-to-Digital Converter (ADC) The raw millivolt signal from the sensor is sent to an ADC. This converts the physical pressure reading into a digital value that the internal microprocessor can read. #### C. Microprocessor (MCU) The MCU handles several tasks: * **Scaling:** Converts the digital signal into units (Bar, PSI, MPa, etc.). * **Logic:** Compares the current pressure against the user-defined "Set Points." * **Display Driver:** Controls the LCD to show real-time data. #### D. NPN Output Circuit The "N" in the suffix usually denotes **NPN output**. * **NPN Open Collector:** When the set pressure is reached, the internal transistor closes the circuit to the negative (0V) line. * **Protection:** These outputs usually include short-circuit protection and reverse polarity protection. --- ### 3. Wiring Diagram (Electronic Interface) For the M2PP series, the standard 4-wire color coding is typically used: | Wire Color | Function | Description | | :--- | :--- | :--- | | **Brown** | L+ | +12 to 24V DC Power | | **Blue** | L- | 0V / Ground | | **Black** | OUT 1 | Digital Output 1 (NPN) | | **White** | OUT 2 | Digital Output 2 (NPN) | --- ### 4. Application Logic The electronic parts allow for several modes of operation: 1. **Hysteresis Mode:** Prevents "chattering" of the switch when pressure fluctuates near the set point. 2. **Window Comparator Mode:** Keeps the output active only within a specific pressure range (e.g., between 0.4 and 0.6 MPa). ---