## FNQ-R-10: Time-Delay Fuse Technical Overview The **FNQ-R-10** is a high-performance, current-limiting time-delay fuse commonly used in industrial and commercial electrical systems. It belongs to the **Class CC** family of fuses, which are known for their compact size and superior rejection capabilities. --- ### 1. Key Specifications | Feature | Specification | | :--- | :--- | | **Amperage Rating** | 10 Amps | | **Voltage Rating (AC)** | 600 Vac | | **Interrupting Rating** | 200,000 Amps RMS Symmetrical | | **Fuse Class** | Class CC | | **Type** | Time-Delay (Slow-Blow) | | **Body Material** | Melamine Tube with Nickel-plated Brass Endcaps | --- ### 2. Functional Characteristics #### A. Time-Delay Feature The "Time-Delay" characteristic allows the fuse to withstand temporary surges in current, such as motor startup inrush or transformer primary surges, without blowing. However, it will still open quickly in the event of a sustained overload or a short circuit. #### B. Current Limiting As a Class CC fuse, the FNQ-R-10 is **current-limiting**. This means it can react extremely fast to a short circuit, stopping the flow of electricity before the current reaches its maximum peak. This protects sensitive downstream electronic components from thermal and magnetic stress. #### C. Rejection Feature The "R" in the part number indicates a **rejection tip**. The physical base of the fuse has a specific shape that prevents it from being replaced by a fuse with a lower voltage or lower interrupting rating, ensuring the safety of the circuit design. --- ### 3. Common Applications * **Control Transformers:** Specifically designed to handle the high inrush currents associated with the primary side of control transformers. * **Motor Control Circuits:** Used in branch circuit protection where space is limited. * **Solenoids and Inductive Loads:** Ideal for circuits that experience frequent switching and inductive spikes. --- ### 4. Physical Dimensions | Dimension | Measurement | | :--- | :--- | | **Length** | 1.5 Inches (38.1 mm) | | **Diameter** | 0.41 Inches (10.3 mm) | ---