The **S500-4-R** is a specific model of a glass tube miniature fuse, typically manufactured by brands like **Eaton (Bussmann Series)**. It is designed for primary circuit protection in various electronic devices. --- ### Technical Specifications Below are the primary electronic characteristics of the S500-4-R: | Feature | Specification | | :--- | :--- | | **Current Rating** | 4 Amperes (4A) | | **Voltage Rating (AC)** | 250 Volts | | **Fuse Speed** | Fast-Acting (F) / Quick Acting | | **Breaking Capacity** | 40A at 250V AC | | **Body Material** | Glass Tube | | **Dimensions** | 5mm x 20mm | | **Termination Style** | Cartridge (Ferrule) | | **RoHS Compliant** | Yes (Indicated by the "-R" suffix) | --- ### Component Breakdown #### 1. Fast-Acting Characteristic As a "Fast-Acting" fuse, the S500-4-R is engineered to open the circuit very quickly when an overcurrent occurs. Unlike "Slow-Blow" (Time-Delay) fuses, it has no tolerance for temporary surges. This makes it ideal for protecting sensitive components like: * Microprocessors * Integrated Circuits (ICs) * Standard Power Supplies #### 2. Physical Construction (5x20mm) This is the standard international size for miniature fuses. The glass body allows for easy visual inspection to see if the internal filament has melted (blown). #### 3. Low Breaking Capacity The S500 series generally features a low breaking capacity. This means it is suited for applications where the potential short-circuit current is relatively low (up to 10 times its rated current). #### 4. The "-R" Suffix In electronic part numbering, the **-R** specifically denotes that the part is **RoHS Compliant** (Restriction of Hazardous Substances), meaning it is manufactured without lead, mercury, cadmium, or other harmful materials. --- ### Common Applications * **Consumer Electronics:** Televisions, audio equipment, and chargers. * **Power Supplies:** Small SMPS (Switched-Mode Power Supplies) units. * **Testing Equipment:** Multimeters and lab power sources.