## Understanding the KTN-R-35 Electronic Part The **KTN-R-35** is a high-performance industrial fuse belonging to the **Limitron™** series, manufactured primarily by **Eaton Bussmann**. It is designed for fast-acting protection in electrical circuits. --- ### 1. Technical Specifications The table below outlines the core electronic and physical characteristics of the KTN-R-35: | Feature | Specification | | :--- | :--- | | **Part Number** | KTN-R-35 | | **Amperage Rating** | 35 Amps | | **Voltage Rating (AC)** | 250 VAC | | **Interrupting Rating** | 200,000 Amps RMS Symmetrical | | **Fuse Class** | Class RK1 | | **Response Speed** | Fast-Acting | | **Physical Size** | 0.81" x 3.0" (Standard Class R dimensions) | | **Termination Style** | Cartridge (Ferrule) | --- ### 2. Key Features and Components The KTN-R-35 is not a simple wire; it is an engineered protective component consisting of several parts: * **Melting Element:** A high-grade silver or copper link designed to melt instantly when current exceeds 35A beyond the specified curve. * **Arc-Quenching Material:** Usually a high-purity silica sand that surrounds the element to absorb heat and extinguish the arc formed during a fault. * **Rejection Feature:** As a **Class RK1** fuse, it features a physical notch in the end cap. This prevents someone from accidentally replacing it with a lower-rated Class H or K fuse, ensuring the high interrupting capacity of the circuit is maintained. * **Housing:** A heavy-duty melamine or fiberglass tube that provides high insulation and structural integrity during high-energy faults. --- ### 3. Primary Applications Because the KTN-R-35 is **Fast-Acting**, it is used in environments where equipment is sensitive to overcurrent and does not have high "inrush" currents (like large motors). 1. **Branch Circuit Protection:** Used in electrical panels to protect specific zones of a building. 2. **Resistive Loads:** Ideal for electric heating elements and lighting circuits. 3. **Semiconductor Protection:** Often used as a primary defense for power electronics and rectifiers. 4. **Control Transformers:** Protecting the secondary side of industrial control transformers. --- ### 4. Comparison: RK1 vs. RK5 It is important to note why the KTN-R (RK1) is chosen over the more common FRN-R (RK5) fuses: * **Current Limitation:** The KTN-R-35 (RK1) is significantly more "current-limiting," meaning it stops a short circuit faster and allows less let-through energy to reach downstream components. * **Safety:** It provides superior protection for circuit breakers and other components that might have lower short-circuit withstand ratings.