The **3AG 2-R** refers to a specific type of electronic component, most commonly identified as a **Fast-Acting Glass Body Cartridge Fuse**. Below is a detailed breakdown of its specifications, physical properties, and common applications. ### 1. General Specifications The alphanumeric code "3AG 2-R" provides information about the size, amperage, and compliance of the fuse. | Attribute | Specification | Description | | :--- | :--- | :--- | | **Series Type** | 3AG | Standard size code (approx. 1/4" x 1-1/4") | | **Current Rating** | 2A | Rated for a maximum of 2 Amperes | | **Voltage Rating** | 250V | Maximum operating voltage | | **Response Characteristic** | Fast-Acting (F) | Opens quickly when current exceeds the rating | | **RoHS Compliant** | -R | Indicates lead-free/environmentally friendly materials | --- ### 2. Physical Dimensions The "3AG" designation is one of the most common physical formats for fuses in North America. * **Diameter:** 6.35 mm (1/4 inch) * **Length:** 31.75 mm (1-1/4 inch) * **Body Material:** Transparent Glass (allows for visual inspection of the filament) * **Cap Material:** Nickel-plated brass or similar conductive alloy --- ### 3. Key Technical Characteristics #### A. Fast-Acting vs. Slow-Blow Unlike "Slo-Blo" fuses (3AB or MDL series), the **3AG 2-R** is designed to blow almost instantly if a short circuit or significant overcurrent occurs. This is critical for protecting sensitive electronic circuits that cannot withstand even brief surges. #### B. Interrupting Rating This component typically has an interrupting rating (breaking capacity) of: * **35A at 250V AC** * **10,000A at 125V AC** #### C. Typical Resistance At a 2A rating, the cold resistance is generally very low (typically in the range of **0.060 to 0.070 Ohms**), ensuring minimal voltage drop across the component during normal operation. --- ### 4. Common Applications The 3AG 2-R fuse is widely used in both consumer and industrial electronics: * **Power Supplies:** Protecting the input stage of desktop equipment. * **Amplifiers:** Used in vintage and modern audio equipment to protect internal circuitry. * **Test Equipment:** Common in multimeters and oscilloscopes. * **Appliances:** Found in small household appliances that require 2A protection. --- ### 5. Part Numbering Example (Littelfuse / Eaton) In a professional context, you may see this part listed under specific manufacturer codes: * **Littelfuse:** `0312002.HXP` (Standard 3AG 2A) * **Bussmann (Eaton):** `BK/AGC-2-R` ---