The **5TTP 125-R** is a specific type of electronic protection component, primarily categorized as a **Time-Lag (Slow Blow) Lead-Free Glass Body Cartridge Fuse**. It is manufactured by **Bel Fuse Inc.** and is part of their 5TTP series. --- ### ## Technical Specifications Below is a detailed breakdown of the technical characteristics of the 5TTP 125-R: | Feature | Specification | | :--- | :--- | | **Current Rating** | 125mA (0.125A) | | **Voltage Rating (AC)** | 250V | | **Fuse Type** | Time-Lag / Slow Blow (T) | | **Body Material** | Glass | | **Size / Dimension** | 5mm x 20mm | | **Termination Style** | Axial Leaded (Pigtail) | | **Interrupting Rating** | 35A @ 250V AC / 10kA @ 125V AC | | **RoHS Status** | Compliant (Lead-Free) | --- ### ## Key Features & Construction #### 1. Axial Leads (Pigtail) Unlike standard cartridge fuses that snap into a clip, the "P" in 5TTP indicates **axial leads**. These are wire leads soldered directly to the end caps, allowing the fuse to be soldered directly onto a Printed Circuit Board (PCB). #### 2. Time-Lag (Slow Blow) Characteristic The "T" designation indicates a "Time-delay" fuse. This means it is designed to withstand short-duration **inrush currents** or surges (common in motors or power supplies) without blowing, but it will disconnect the circuit if a sustained overload occurs. #### 3. Glass Body The transparent glass body allows for easy visual inspection. If the fuse has blown due to a major short circuit, the internal filament will be visibly broken or the glass may appear charred. --- ### ## Common Applications The 5TTP 125-R is typically used in low-power electronic devices where sensitive circuitry needs protection from overcurrent but requires a delay to prevent "nuisance tripping" during startup. * **Power Supplies:** Protecting the primary side of small AC/DC adapters. * **Consumer Electronics:** Used in TVs, chargers, and audio equipment. * **Industrial Controls:** Protecting low-current control loops and sensors. * **LED Lighting:** Drivers that experience initial current spikes. --- ### ## Meaning of the Part Number * **5TTP**: The Series name (5x20mm, Time-lag, Pigtail/Axial). * **125**: Represents the current rating (125mA). * **-R**: Indicates RoHS compliance (Lead-free).