The **47LAC-242W-R** is a specific model of an **Electromagnetic Buzzer** (also known as a magnetic transducer or sounder). These components are widely used in consumer electronics, medical devices, and industrial control panels to provide acoustic feedback or alarms. Below is a detailed breakdown of its specifications and electronic characteristics. ### 1. Technical Specifications The following table highlights the typical parameters for this series of electromagnetic buzzers: | Parameter | Specification (Typical) | | :--- | :--- | | **Type** | Electromagnetic / Magnetic Transducer | | **Rated Voltage** | 24V DC (Indicated by '24' in part number) | | **Operating Voltage** | 15V ~ 28V DC | | **Rated Current** | Max 40mA | | **Sound Pressure Level (SPL)** | Min 85 dB (at 10cm distance) | | **Resonant Frequency** | 2400 Hz ± 300Hz | | **Housing Material** | PBT / NORYL (High temperature resistant) | | **Mounting Type** | Through-hole (Pins) | | **RoHS Compliant** | Yes (Indicated by '-R') | --- ### 2. Physical Construction The part is designed for PCB (Printed Circuit Board) integration. Its physical attributes generally include: * **Internal Circuitry:** This model is usually an **Indicator type** (Internal Drive), meaning it has a built-in oscillation circuit. You only need to apply a DC voltage to make it sound. * **Dimensions:** Typically 12mm in diameter and 9.5mm in height (Standard "Washable" size). * **Sealing:** The "W" in the part number often signifies a **Washable** design, featuring a removable sticker over the top hole to prevent fluid ingress during the PCB soldering/washing process. --- ### 3. Electronic Operation To integrate the 47LAC-242W-R into a circuit, consider the following electronic principles: #### Powering the Device Since this is a 24V component, it requires a higher voltage than standard 5V microcontrollers. A transistor switching circuit is required. #### Example Circuit Code (Arduino/Microcontroller) If you are controlling the buzzer via a 24V supply and a logic-level NPN transistor (like a 2N2222): ```cpp const int buzzerPin = 9; // Connected to the base of the transistor void setup() { pinMode(buzzerPin, OUTPUT); } void loop() { digitalWrite(buzzerPin, HIGH); // Buzzer turns ON delay(1000); // Sound for 1 second digitalWrite(buzzerPin, LOW); // Buzzer turns OFF delay(1000); // Silence for 1 second } ``` --- ### 4. Application Use Cases * **Industrial Equipment:** Status indicators for 24V PLC systems. * **Automotive Electronics:** Warning chimes for heavy machinery or trucks. * **Appliances:** High-voltage control boards for white goods. ---