The **LC4H-R4-AC240V** is a sophisticated digital electronic timer manufactured by Panasonic (formerly Matsushita/National). It belongs to the LC4H series and is characterized by its bright, 4-digit LED display and versatile mounting options. Below is a detailed breakdown of its electronic components, specifications, and features. --- ### 1. Technical Specifications The model name itself encodes the primary electrical characteristics: | Feature | Specification | | :--- | :--- | | **Series** | LC4H (Digital Electronic Counter/Timer) | | **Output Type** | **R**: Relay Output (1c contact) | | **Number of Digits** | **4**: 4-digit LED display (ranges up to 999.9 or 99h59m) | | **Operating Voltage** | **AC240V**: 100V to 240V AC (50/60 Hz) | | **Mounting Style** | Panel mount (standard 48mm x 48mm DIN size) | | **Terminal Type** | 11-pin cylindrical base (Plug-in) | --- ### 2. Internal Electronic Components The device functions as a specialized microcontroller-based timing relay. Key internal parts include: #### A. Power Supply Unit (PSU) * **Transformerless Capacitive Dropper / SMPS:** Converts the 240V AC input into low-voltage DC (typically 5V or 12V) to power the internal logic and display. * **Smoothing Capacitors:** High-grade electrolytic capacitors ensure stable DC current to prevent flickering or logic errors during voltage fluctuations. #### B. The Logic Controller * **Microprocessor:** An embedded MCU handles the timing algorithms, scale conversions, and user input from the front-facing membrane buttons. * **EEPROM:** Non-volatile memory that stores user-set time values and configuration settings, ensuring they are not lost during a power failure. #### C. Output Mechanism * **Electromechanical Relay:** The "R" in the model name indicates a physical relay. * **Contact Rating:** Typically 5A at 250V AC (Resistive load). * **Configuration:** Single-pole, double-throw (SPDT / 1c). #### D. User Interface (Front Panel) * **LED Display:** A high-contrast 7-segment LED (Red/Green) that shows the elapsed time or remaining time. * **Operation Keys:** Sealed tactile switches for UP/DOWN settings and Mode selection. --- ### 3. Pin Configuration (11-Pin Base) The LC4H-R4 uses an 11-pin layout. The electronic connections are generally mapped as follows: | Pin Number | Function | | :--- | :--- | | **2 & 10** | Power Supply Input (100-240V AC) | | **1, 3, 4** | Relay Contacts (Common, NO, NC) | | **5, 6, 7** | Control Inputs (Stop, Reset, Start) | | **9, 11** | Signal Ground / Common for Inputs | --- ### 4. Key Electronic Features * **IP66 Protection:** The front panel is electronically sealed against dust and water jets, making it suitable for industrial environments. * **Multi-mode Operation:** The internal circuitry supports multiple timing modes: * On-delay / Off-delay * Flicker (Oscillating) * One-shot * Integration * **Changeable Brightness:** The LED brightness can be adjusted via the internal software settings to suit ambient light conditions. ---