The **KTN-R-500** is a high-capacity, industrial-grade fuse. It belongs to the **Class RK1** family of fuses, which are known for their high degree of current limitation and safety. --- ### 1. Technical Specifications The following table outlines the core electrical characteristics of the KTN-R-500: | Feature | Specification | | :--- | :--- | | **Amperage Rating** | 500 Amps | | **Voltage Rating** | 250 Volts AC | | **Interrupting Rating** | 200,000 Amps RMS Symmetrical | | **Fuse Class** | Class RK1 | | **Type** | Fast-Acting | | **Body Material** | Melamine or Fiberglass tube | | **Terminal Material** | Silver-plated Copper | --- ### 2. Key Component Features #### High Interrupting Capacity The KTN-R-500 is rated to safely interrupt up to **200,000 Amps**. This means it can safely break a circuit during a massive short-circuit event without exploding or causing damage to the surrounding enclosure. #### Fast-Acting Operation Unlike "Time-Delay" fuses (which allow brief surges for motor startups), the KTN-R-500 is **Fast-Acting**. It is designed to open almost instantly when it senses an overcurrent, making it ideal for protecting sensitive electronic components or resistive loads. #### Current Limitation As an RK1 fuse, it is "Current Limiting." This means it physically prevents the peak fault current from ever reaching its full potential, significantly reducing the thermal and magnetic stress on downstream equipment. --- ### 3. Physical Construction * **Blade Terminals:** Due to its 500A rating, this fuse uses large "knife-blade" style terminals rather than cylindrical ferrules. * **Rejection Feature:** The "R" in KTN-R indicates a rejection notch. When used with a Class R fuse block, it prevents the accidental installation of lower-rated fuses (like Class H or K) into the circuit. * **Arc Quenching Filler:** The interior is typically filled with high-purity silica sand, which absorbs the energy of an electrical arc when the internal element melts. --- ### 4. Common Applications * **Main Service Switches:** Used in large building electrical entrances. * **Feeder Circuits:** Protecting secondary power distribution panels. * **Non-Inductive Loads:** Ideal for electric heating systems or lighting circuits where high inrush currents are not present. * **DC Rectifiers:** Often used in industrial power supplies.