## Overview of the 5TTP 300-R The **5TTP 300-R** is a specific type of electronic component, primarily identified as a **Time-Lag (Slow Blow) Glass Body Cartridge Fuse**. It is part of the 5TTP series manufactured by Bel Fuse Inc. ### Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Current Rating** | 300 mA (0.3 Amps) | | **Voltage Rating (AC)** | 250 V | | **Fuse Type** | Time-Lag / Slow Blow (T) | | **Size / Dimension** | 5mm x 20mm (Standard Small Cartridge) | | **Body Material** | Glass | | **Termination Style** | Pigtail (Axial Leaded) | | **Breaking Capacity** | 35A @ 250V AC / 10,000A @ 125V AC | --- ### Core Characteristics #### 1. Time-Lag (Slow Blow) Functionality Unlike "Fast-Acting" fuses, the 5TTP 300-R is designed to withstand temporary surges in current. This is crucial for circuits that experience high "inrush current" when a device is first turned on (such as motors or power supplies). The fuse will only blow if the overcurrent persists, preventing nuisance tripping. #### 2. Axial Pigtail Leads The "-R" suffix and the "P" in the part number usually signify the inclusion of **Pigtail leads**. These are wire leads attached to the end caps, allowing the fuse to be soldered directly onto a Printed Circuit Board (PCB) rather than being inserted into a fuse holder. #### 3. Material Composition * **Glass Tube:** Allows for visual inspection to see if the internal element is broken. * **Nickel-Plated Brass Caps:** Ensure high conductivity and corrosion resistance. * **Lead-Free (RoHS Compliant):** The "R" in Bel Fuse nomenclature also confirms that the part complies with environmental regulations regarding hazardous substances. --- ### Common Applications Due to its low amperage and slow-blow nature, this component is frequently found in: * **Power Supplies:** Protecting the primary side of small AC/DC adapters. * **Consumer Electronics:** Televisions, audio equipment, and chargers. * **Industrial Controls:** Low-power circuit protection for sensors or controllers. --- ### Component Identification Code The part number can be broken down as follows: * **5TT:** Represents the series (5x20mm, Time-lag). * **P:** Indicates Pigtail (Axial Leads). * **300:** Represents the current rating (300mA). * **-R:** Indicates RoHS compliance.