The **CJT20-1003JB** is a specific type of passive electronic component, primarily categorized as a **Wirewound Power Resistor**. These components are designed to dissipate significant heat while maintaining a stable resistance value. Below is a detailed breakdown of its specifications and characteristics. --- ### 1. Part Number Breakdown The part number follows a standard convention for the CJT series: | Segment | Meaning | Detail | | :--- | :--- | :--- | | **CJT** | Series Name | Aluminum Housed Wirewound Resistor | | **20** | Power Rating | 20 Watts | | **1003** | Resistance Code | 100 x 10³ = **100,000 Ω (100kΩ)** | | **J** | Tolerance | ±5% | | **B** | Packaging/Form | Bulk / Standard Bracket Mount | --- ### 2. Technical Specifications This resistor is built for durability and high-stress environments. | Parameter | Specification | | :--- | :--- | | **Resistance Value** | 100 kΩ | | **Power Rating** | 20 Watts (at 25°C) | | **Tolerance** | ± 5% | | **Casing Material** | Anodized Aluminum | | **Termination Style** | Solder Lug / Wire Lead | | **Temperature Coefficient** | Typically ±260 ppm/°C | | **Max Operating Voltage** | ~350V - 500V (depending on insulation) | --- ### 3. Key Physical Features * **Aluminum Housing:** The resistive element is encased in an extruded aluminum shell. This acts as a heat sink, allowing the component to dissipate 20W of power efficiently when mounted to a metal surface. * **Wirewound Core:** The internal element consists of a resistive wire wound around a ceramic core. This construction is robust against high-energy pulses and surges. * **Encapsulation:** The internal assembly is usually sealed with a high-temperature silicone or cement filler to protect against moisture and vibration. --- ### 4. Common Applications Due to its high power rating and 100kΩ resistance, the CJT20-1003JB is typically used in: 1. **Bleeder Resistors:** Discharging high-voltage capacitors in power supplies for safety. 2. **Voltage Dividers:** Used in industrial sensing circuits where high voltage needs to be stepped down. 3. **Inrush Current Limiting:** Protecting circuits from sudden power spikes. 4. **Load Simulation:** Used in testing circuits that require a specific 100kΩ load. --- ### 5. Installation Note To achieve the full **20W power rating**, this resistor **must be mounted to a heat sink** (such as a metal chassis). Without proper heat sinking, the resistor will overheat and may fail or drift in value if operated at its maximum rated power.