## Overview of PSI-MOS-DNET Electronic Parts The **PSI-MOS-DNET** series from Phoenix Contact consists of fiber optic converters specifically designed for **DeviceNet** and **CANopen** systems. These devices convert electrical copper-based signals into optical signals, allowing for interference-free communication over long distances. --- ### Core Hardware Components The internal electronics of these modules are divided into three functional areas: the fieldbus interface, the optical interface, and the diagnostic/power management circuit. | Component Group | Part Type | Function | | :--- | :--- | :--- | | **Fieldbus Interface** | D-SUB / Terminal Block | Connects to the copper DeviceNet/CANopen network. | | **Optical Transceivers** | F-ST or FSMA Connectors | Converts electrical signals to light pulses (LED/Laser). | | **Status Indicators** | Diagnostic LEDs | Visual feedback for FO quality, power, and data traffic. | | **Configuration** | DIP Switches | Sets baud rate, network termination, and operating modes. | | **Power Supply** | 24V DC Terminals | Provides power via system bus connectors or terminals. | --- ### Technical Specifications (Electronic) The electronics are engineered to handle high-speed data while providing galvanic isolation. * **Baud Rate Support:** Auto-detection or manual setting (up to 1 Mbps). * **Wavelength:** Usually **660 nm** (Red light) for Polymer fibers or **850 nm** for Glass fibers. * **Galvanic Isolation:** The RS-485/CAN interface is typically isolated from the power supply and the optical side to prevent ground loops. * **Signal Delay:** Ultra-low latency electronics to ensure the CAN arbitration mechanism remains functional. --- ### Diagnostic Logic: The "Bargraph" Display One of the unique electronic features of the PSI-MOS series is the **integrated optical diagnostics**. 1. **Optical Power Monitoring:** The internal circuitry measures the incoming light intensity. 2. **Bargraph Output:** A set of LEDs (Yellow/Green) indicates the quality of the fiber connection. 3. **Alarm Relay:** A physical dry contact (relay) triggers if the signal quality drops below a critical threshold, allowing for predictive maintenance. --- ### Typical Circuit Setup ```mermaid graph LR A[Copper DeviceNet] --> B[Isolation Barrier] B --> C[Protocol Logic Chip] C --> D[Optical Driver] D --> E[Fiber Optic Cable] F[Power 24V] --> B F --> C ``` --- ### Connection Methods 1. **D-SUB 9:** Standard CANopen/DeviceNet pin assignment. 2. **COMBICON:** Plug-in screw terminals for power and basic signaling. 3. **DIN Rail Connector:** Allows for "modular" power bridging, where one power supply feeds multiple units through the rail.