The **KTK-R-5** is a specific type of industrial fuse manufactured by companies like Bussmann (Eaton). It belongs to the **Limitron™** series and is designed for high-performance circuit protection. --- ## 1. Technical Specifications The following table outlines the core electronic and physical characteristics of the KTK-R-5 fuse: | Feature | Specification | | :--- | :--- | | **Current Rating** | 5 Amps | | **Voltage Rating (AC)** | 600 Vac | | **Interrupting Rating** | 200,000 Amps (200 kA) RMS Symmetrical | | **Fuse Class** | Class CC | | **Speed/Response** | Fast-Acting | | **Body Material** | Melamine (Fiberglass) tube with Nickel-plated brass endcaps | | **Dimensions** | 13/32" x 1-1/2" (10.3mm x 38.1mm) | --- ## 2. Key Design Features ### Rejection Feature (The "R" in KTK-R) The "R" designation stands for **Rejection**. These fuses feature a unique physical "groove" or rejection tip on one of the endcaps. * **Purpose:** This prevents the installation of a lower-rated or incorrect class of fuse into a Class CC fuse holder, ensuring the safety integrity of the circuit. ### Fast-Acting Performance Unlike "Time-Delay" fuses, the KTK-R-5 is **Fast-Acting**. * It is designed to open (blow) very quickly when it detects an overcurrent or short-circuit condition. * This makes it ideal for protecting sensitive components that cannot withstand prolonged surges. --- ## 3. Common Applications The KTK-R-5 is typically used in industrial and commercial electrical environments: * **Control Circuits:** Protection of control transformers and small motors. * **Lighting Ballasts:** Protecting high-voltage lighting systems. * **Branch Circuit Protection:** General-purpose protection where high interrupting capacity is required. * **Sensitive Electronics:** Used in panels where quick disconnection is necessary to prevent fire or equipment destruction during a fault. --- ## 4. Comparison: KTK vs. KTK-R It is important to distinguish between the standard KTK and the KTK-R: | Feature | KTK (Standard) | KTK-R (Rejection) | | :--- | :--- | :--- | | **Endcap Style** | Flat cylindrical ends | One end has a rejection tip (groove) | | **Safety Class** | Supplemental | Branch Circuit (Class CC) | | **Code Compliance** | UL Listed | UL Listed & meets NEC for branch circuits |