## FNQ-R-2 Electronic Component Overview The **FNQ-R-2** is a high-performance, current-limiting industrial fuse belonging to the **CC-TRON™** family. It is specifically designed for branch circuit protection and is widely used in control systems. --- ### Technical Specifications | Property | Description | | :--- | :--- | | **Manufacturer** | Bussmann (Eaton) | | **Current Rating** | 2 Amperes | | **Voltage Rating (AC)** | 600 Vac | | **Interrupting Rating** | 200,000 Amps RMS Symmetrical | | **Fuse Class** | Class CC | | **Response Characteristic** | Time-Delay (Slow-Blow) | | **Construction** | Melamine tube with nickel-plated brass endcaps | --- ### Key Electronic Features #### 1. Rejection Feature The "R" in the part number signifies a **rejection tip**. This physical design prevents the installation of lower-rated or incorrect fuse classes into a Class CC fuse holder, ensuring the integrity of the circuit protection. #### 2. Time-Delay Functionality The FNQ-R-2 is engineered to handle **inrush currents**. In circuits involving small control transformers or inductive loads, the current may briefly spike well above 2A during startup. This fuse allows those transient peaks without blowing, while still protecting against sustained overloads. #### 3. High Current Limitation As a Class CC fuse, it is "current-limiting." In the event of a catastrophic short circuit, the fuse reacts in less than half a cycle, preventing the peak fault current from reaching its maximum potential. This protects downstream sensitive electronics from thermal and magnetic stress. --- ### Typical Applications * **Control Transformers:** Protecting the primary side of industrial control transformers. * **Solenoids:** Managing the high inductive kickback and startup draw. * **Motor Control:** Branch circuit protection for small motor loads. * **PLC I/O:** Safeguarding programmable logic controller inputs/outputs. --- ### Comparison with Similar Fuses | Feature | FNQ-R (Class CC) | FNQ (Midget) | | :--- | :--- | :--- | | **Rejection Tip** | Yes | No | | **Interrupting Rating** | 200kA | 10kA | | **Voltage Rating** | 600V | 500V | | **Usage** | Critical Branch Circuits | Supplemental Protection |