The **QO2125VH2100** is a specialized, high-capacity sub-assembly or "sub-feed" circuit breaker system manufactured by **Schneider Electric (Square D)**. It is part of the QO (Quick-Open) product line, renowned for its reliability and "Visi-Trip" indicator. ### Core Specifications Below is a breakdown of the primary electrical characteristics of this specific unit: | Feature | Specification | | :--- | :--- | | **Manufacturer** | Square D (Schneider Electric) | | **Product Type** | Miniature Circuit Breaker (MCB) | | **Amperage (Main)** | 125 Amp | | **Amperage (Sub-feed)** | 100 Amp | | **Voltage Rating** | 120/240V AC | | **Interrupt Rating** | 22 kA (High Interrupting Capacity) | | **Number of Poles** | 2-Pole | | **Mounting Type** | Plug-On | --- ### Component Breakdown & Electronic Functions #### 1. Thermal-Magnetic Trip Mechanism This part uses two distinct methods for circuit protection: * **Thermal Protection:** Uses a bimetallic strip that bends when heated by a consistent overload (e.g., running too many appliances). This handles long-term overcurrent. * **Magnetic Protection:** Uses an internal electromagnetic coil that reacts instantly to short circuits. When a massive surge is detected, the magnetic field pulls the trip bar immediately. #### 2. The "VH" Designation (High Interrupting Capacity) The "VH" in the part number indicates a **High Interrupt Rating**. * Standard QO breakers usually handle up to 10 kA. * The **VH** version is rated for **22 kA**. This means the internal components (arc chutes and contacts) are reinforced to safely extinguish a much larger electrical arc without exploding or welding the contacts together. #### 3. Sub-Feed Functionality The unique aspect of the QO2125VH2100 is that it often functions as a **Sub-feed Lug** or a breaker-base combination. It is designed to be installed in a load center to feed power to another downstream panel (sub-panel). It effectively acts as a 125A frame containing 100A protection. #### 4. Visi-Trip Indicator One of the mechanical/electronic feedback features is the red "Visi-Trip" flag. When the internal mechanism trips due to a fault, a high-visibility red indicator appears in the window, allowing for instant troubleshooting. --- ### Wiring and Connection Technicals The device uses pressure plate terminals designed for high-gauge copper or aluminum wire. ```markdown Wire Size Compatibility: - AWG 4 to AWG 2/0 (Aluminium/Copper) - Torque Requirement: ~50 lb-in (Note: Always check the label on the specific unit) ``` ---