The **Moxa PT-7828-R-HV** is a high-performance, Layer 2 managed Ethernet switch designed specifically for power substation automation. It adheres to the **IEC 61850-3** and **IEEE 1613** standards. Below is a breakdown of its electronic components, power specifications, and hardware architecture. --- ### 1. Power Supply System (HV Model) The "HV" in the model name stands for **High Voltage**. This unit is designed to operate within industrial and utility power grids. | Feature | Specification | | :--- | :--- | | **Input Voltage** | 110/220 VAC/VDC (88 to 300 VDC, 85 to 264 VAC) | | **Redundancy** | Dual isolated redundant power supplies (Rear cabling) | | **Protection** | Built-in Overload Current & Reverse Polarity Protection | | **Isolation** | 3 kVDC or 2 kVrms isolation for power ports | ### 2. Modular Hardware Architecture The PT-7828 is a **modular switch**, meaning its electronic capabilities depend on the interface modules inserted into the chassis. * **Fixed Slots:** Usually 4 slots for 4-port modules. * **Total Ports:** Up to 28 ports (24 Fast Ethernet + 4 Gigabit). * **Module Types:** * **PM-7200 Series:** Includes 10/100BaseT(X) copper, multi-mode fiber (ST/SC), and single-mode fiber options. * **Gigabit Modules:** Slots for SFP or Copper Gigabit uplinks to handle backbone traffic. ### 3. Core Electronic Components & Logic The internal circuitry is hardened for extreme electromagnetic interference (EMI). * **Switching Fabric:** Non-blocking crossbar architecture to ensure zero packet loss at full wire speed. * **Storage/Memory:** Internal Flash for firmware and configuration; RAM for packet buffering (critical for GOOSE messaging in substations). * **Physical Layer (PHY):** Industrial-grade transceivers designed to withstand surges and electrostatic discharge (ESD). * **Passive Cooling:** The electronic design utilizes a fanless heat-sink system to increase MTBF (Mean Time Between Failures). ### 4. Technical Hardware Specifications | Component | Detail | | :--- | :--- | | **Housing** | IP30 aluminum/steel protection | | **Console Port** | RS-232 (RJ45 connector) for local management | | **Alarm Contact** | 1 relay output with current carrying capacity of 1A @ 24VDC | | **Operating Temp** | -40 to 85°C (-40 to 185°F) - Wide temperature rated | --- ### 5. Critical Compliance Electronics The internal electronic filtering is designed to pass: * **IEC 61000-4-2 (ESD):** Level 4. * **IEC 61000-4-4 (EFT):** Level 4. * **IEC 61000-4-5 (Surge):** Level 4. * **IEEE 1613:** Error-free communication under EMI stress.