The **DMS-30DR-2-R-C** is a high-precision, 3.5 digit digital voltmeter manufactured by Murata Power Solutions (formerly Datel). It is part of the DMS-30DR series, known for being self-contained, rugged, and easy to mount. --- ### ## Technical Specifications Breakdown The part number "DMS-30DR-2-R-C" provides specific information about its electronic characteristics: | Code Segment | Specification | Description | | :--- | :--- | :--- | | **DMS-30DR** | Series Base | 3.5 Digit, LED Display, Digital Panel Meter | | **-2** | Input Range | ±2V (DC) Full Scale Input | | **-R** | LED Color | Red (Standard Intensity) | | **-C** | Compliance | RoHS Compliant | --- ### ## Key Electronic Components & Features ### 1. The Analog-to-Digital Converter (ADC) At the heart of this module is a dual-slope integration A/D converter. This provides: * **High Noise Rejection:** Excellent immunity to 50/60Hz line noise. * **Auto-Zeroing:** The circuit automatically zeros itself between conversion cycles to maintain accuracy. * **Input Impedance:** Typically **1,000 MΩ**, ensuring minimal loading on the circuit being measured. ### 2. The Display System * **Display Type:** 3.5 Digit LED (meaning it can display up to "1999"). * **Character Height:** 0.56 inches (14.2mm). * **Polarity Indication:** Automatically displays a minus sign (-) for negative inputs. * **Overrange Indication:** The display will flash or show a "1" followed by three blank digits if the input exceeds ±1.999V. ### 3. Power Requirements * **Operating Voltage:** Typically +5V DC (regulated). * **Current Consumption:** Usually ranges between 100mA to 150mA depending on the number of LED segments lit. ### 4. Signal Connections The unit typically uses a **12-pin dual-in-line (DIP)** configuration. Key pins include: * **Pin 1 (+5V Supply):** Main power input. * **Pin 11 & 12 (HI/LO Inputs):** The differential inputs where the ±2V signal is applied. * **Decimal Point Select:** Pins are available to manually set the decimal point position via external jumpers. --- ### ## Operational Summary * **Accuracy:** ±0.05% of full scale ±1 count. * **Sampling Rate:** Approximately 3 samples per second. * **Operating Temperature:** 0°C to +60°C. * **Common Mode Rejection:** 80dB (DC to 60Hz).