The **KWDY-1F-R** is a high-sensitivity, subminiature PCB-mount signal relay commonly used in telecommunications, security systems, and medical equipment. It is designed for low-power switching applications where space is limited. --- ### ## Technical Specifications Below are the primary electronic characteristics of the KWDY-1F-R: | Feature | Specification | | :--- | :--- | | **Contact Form** | 1 Form C (SPDT - Single Pole Double Throw) | | **Contact Material** | Gold-clad Silver Alloy | | **Max Switching Voltage** | 125VAC / 60VDC | | **Max Switching Current** | 1A (AC) / 2A (DC) | | **Nominal Coil Power** | Approximately 150mW to 200mW (High Sensitivity) | | **Dielectric Strength** | 500VAC (between open contacts) | | **Life Expectancy** | 100,000 operations (Electrical) | --- ### ### Key Components and Construction 1. **Electromagnetic Coil:** The core of the relay. When a specific DC voltage is applied, it creates a magnetic field that pulls the armature. The "R" in the suffix often denotes high sensitivity, meaning it requires very little current to trigger. 2. **Contacts (Gold-Clad):** Because this is a signal relay, the contacts are gold-clad. This prevents oxidation and ensures a reliable connection when switching very low-level signals (dry circuits). 3. **Sealed Structure:** The "1F" usually indicates a wash-tight or flux-proof plastic sealed construction. This allows the part to be cleaned on a PCB production line without chemicals entering the internal mechanism. 4. **Terminals:** Standard PCB through-hole pins arranged in a DIP (Dual In-line Package) footprint for easy integration into circuit boards. --- ### ### Typical Application Circuit In a typical electronic circuit, the KWDY-1F-R is used as an interface between a low-power microcontroller (MCU) and a load. ```cpp // Example: Driving the relay via a Transistor [MCU Pin] ---> [1k Resistor] ---> [Base of NPN Transistor (e.g. 2N2222)] [Collector] ---> [Relay Coil Pin 1] [Emitter] ---> [GND] [VCC] ---------------------------> [Relay Coil Pin 2] // Note: Always place a Flyback Diode (1N4148) across the coil pins! ``` --- ### ### Pinout Configuration (General) Most relays in this series follow a standard subminiature footprint: * **Pins 1 & 5:** Coil connections. * **Pin 2:** Common (COM). * **Pin 3:** Normally Closed (NC). * **Pin 4:** Normally Open (NO).