The **EX87424-R21W** is an industrial-grade, managed Ethernet switch designed primarily for harsh environments such as power substations, transportation systems, and industrial automation. It belongs to the EtherWAN EX87000 series. Below is a breakdown of its electronic components, specifications, and architecture. --- ### 1. Port Configuration & Hardware Interface The device is characterized by its high-density port layout and modular flexibility. | Component | Specification | | :--- | :--- | | **Copper Ports** | 24 x 10/100BASE-TX (RJ45) | | **Combo/Uplink Ports** | 4 x Gigabit Combo (10/100/1000BASE-T or SFP slots) | | **Console Port** | 1 x RS-232 (RJ45) for out-of-band management | | **Alarm Contact** | 1 x Relay output (24VDC @ 1A) for event notification | ### 2. Processing and Switching Architecture The internal electronic architecture is designed for high-speed packet processing and low latency. * **Switching Capacity:** Typically 12.8 Gbps non-blocking fabric, ensuring all ports can operate at wire speed simultaneously. * **MAC Address Table:** Supports up to 8,000 entries, allowing it to handle large industrial networks. * **Packet Buffer:** Built-in memory (usually 2Mbits to 4Mbits) to prevent data loss during traffic bursts. * **Management Processor:** An embedded RISC-based processor handles the firmware, SNMP, and web management interface. ### 3. Power Supply Units (PSU) The "R21W" suffix usually denotes specific power configurations: * **Input Voltage:** Redundant power inputs (often 100-240VAC or high-voltage DC options). * **Protection:** Integrated OVP (Over Voltage Protection) and reverse polarity protection. * **Isolation:** High-level isolation between power circuits and data ports to prevent damage from surges. ### 4. Environmental & Physical Electronics The electronic components are chosen for "Hardened" specifications: * **Temperature Grade:** Components are rated for **-40°C to 75°C** (-40°F to 167°F) operation. * **Housing:** Fanless design utilizing a metal chassis as a heat sink to prevent mechanical failure points. * **PCB Coating:** Often includes conformal coating options to protect against humidity and corrosion. ### 5. Compliance and Standards The electronics are tested to meet rigorous industrial standards: * **IEEE 802.3x:** Flow Control. * **IEEE 802.1p:** Quality of Service (QoS). * **IEC 61850-3 / IEEE 1613:** Standards for electronic equipment in power substations (EMI/EMC immunity). ---