The **PPD-D1N1R-R** is a specific model of a **Digital Pressure Sensor** typically manufactured by companies like **Koganei**. These sensors are used in industrial automation to monitor and control air or gas pressure in pneumatic systems. --- ### 1. Technical Specifications The part number defines the physical and electrical characteristics of the unit. Below is a breakdown of its primary specifications: | Feature | Specification | | :--- | :--- | | **Pressure Range** | Positive Pressure (usually 0 to 1.0 MPa) | | **Output Type** | NPN Open Collector (Digital) | | **Analog Output** | 1 to 5V DC (Integrated) | | **Port Size** | R1/8 (Tapered Pipe Thread) | | **Operating Voltage** | 12 to 24V DC | | **Display Type** | 3.5 digit, 2-color LED (Red/Green) | --- ### 2. Key Electronic Components & Internal Design The PPD-D1N1R-R consists of several internal electronic subsystems: * **Pressure Transducer (Piezo-resistive Element):** This is the core sensing element. It converts mechanical pressure into a small electrical signal. * **A/D Converter & Microcontroller:** The analog signal from the transducer is converted into digital data, allowing the onboard processor to compare the current pressure against the user-defined "Set Point." * **Dual-Output Transistors (NPN):** * Since it is an **NPN** type, the output acts as a "sink." When the pressure reaches the threshold, the sensor connects the load to the Negative (OV) rail. * **Analog Output Circuit:** It provides a 1-5V linear signal corresponding to the pressure range, which can be sent to a PLC (Programmable Logic Controller) for data logging or PID control. --- ### 3. Wiring Configuration The device typically uses a 4-wire or 5-wire lead. The standard color coding is as follows: | Wire Color | Function | Description | | :--- | :--- | :--- | | **Brown** | V+ | Power Supply (12-24V DC) | | **Blue** | 0V | Power Supply Ground | | **Black** | OUT 1 | Digital Output (NPN) | | **White** | Analog | 1-5V Analog Output | --- ### 4. Functional Features * **Hysteresis Mode:** Prevents the output from "chattering" when the pressure fluctuates rapidly around the set point. * **Color Change Display:** The LED screen can be programmed to change from Green to Red when a specific pressure limit is exceeded, providing immediate visual feedback to operators. * **Auto-set Function:** Simplifies the calibration process by allowing the sensor to learn the "high" and "low" points of an application automatically. ---