### Overview of FPK-R-15A The **FPK-R-15A** is a specific model of a **Class CC Time-Delay Fuse**. These components are critical in industrial electronics for protecting branch circuits, control transformers, and small motor loads. --- ### Technical Specifications | Parameter | Specification | | :--- | :--- | | **Series** | FPK (Class CC) | | **Current Rating** | 15 Amperes | | **Voltage Rating (AC)** | 600 VAC | | **Voltage Rating (DC)** | 300 VDC | | **Interrupting Rating** | 200,000A at 600VAC | | **Response Characteristic** | Time-Delay (Slow Blow) | | **Physical Size** | 13/32" x 1-1/2" (Standard Midget size) | --- ### Key Features and Functionality #### 1. Rejection Feature (Class CC) The "R" in the part number signifies the **rejection tip**. This is a physical modification on the end of the fuse that prevents the installation of lower-rated fuses (like standard midget fuses) into a Class CC fuse holder. This ensures the safety of the circuit is not compromised by an incorrect fuse type. #### 2. Time-Delay Mechanism Unlike a "Fast-Acting" fuse, the FPK-R-15A can handle temporary **inrush currents**. * **Startup Peaks:** It will not blow when a motor or transformer starts up and draws a momentary spike of current. * **Sustained Overload:** It will blow if the 15A limit is exceeded for a prolonged period, protecting the wiring from overheating. #### 3. High Interrupting Capacity With a rating of **200,000 Amps**, this fuse is designed to safely open even under massive short-circuit conditions without exploding or causing an arc-flash hazard in industrial control panels. --- ### Internal Electronic Composition The internal structure typically consists of: * **Dual-Element Construction:** Often utilizes a heat-sensitive solder joint (for overloads) and a notched fuse link (for short circuits). * **Arc-Quenching Material:** The body is filled with high-grade silica sand to extinguish the electrical arc that occurs when the fuse blows. * **Melamine/Fiberglass Tube:** Provides high insulation and thermal resistance. --- ### Typical Applications * **Industrial Control Panels:** Protecting PLC outputs and control power transformers. * **Small Motors:** Used as branch circuit protection for fractional horsepower motors. * **HVAC Systems:** Protection for fans and compressor control circuits.