www.murata-ps.com DMU-30DCV Series Ruggedized DC Voltmeters with Daylight Readable Auto-Dimming LED Displays Murata Power Solutions DMU-30DCV series of daylight-readable dc voltmeters measure and display dc signals as low as 200mV and as high as 200V. Their large 0.56 (14.2mm) high super-bright red LED-display is readable in full sunlight. An auto-dimming circuit automatically adjusts the display brightness for all viewing conditions. DMU-30DCV series dc voltmeters are packaged in a rugged, one-piece polycarbonate plastic housing that features an integrated bezel and gasket assembly. In a typical instal- lation, the housing is secured to a panel with six metallic threaded inserts, allowing the unit to meet NEMA-4 / IP65 requirements for moisture and impact resistance in outdoor applications. DMU-30DCV series dc voltmeters are available in a choice of four input ranges: FEATURES 200mVdc (with 0.1mV resolution) 2Vdc (0.001V resolution) 20Vdc (0.01V resolution) Measure and accurately display dc voltages in harsh and 200Vdc (0.1V resolution). The dc signal under measurement is electrically isolated environments from the units operating power source. DMU-30DCV series miniature size and rugged package are perfect for industrial and Four input ranges: 200mVdc, 2Vdc, 20Vdc, and high-reliability instrumentation, alternative power generators, and any other application 200Vdc which requires daylight readability and precise monitoring of dc voltages in harsh indoor / Daylight-readable LED display with automatic outdoor environments. Simply connect the input signal and an 85-264Vac source of operat- brightness adjustment ing power to the two rear-mounted terminal blocks and the unit is fully operational. Moisture & impact resistant package offers NEMA-4/IP65 protection Operates from universal 85-264Vac mains, or 110-300Vdc supplies TECHNICAL NOTES Input circuit fully isolated from ac power supply IMPORTANT To ensure safe and reliable operation, DMU-30DCV dc voltmeters must be installed and serviced by quali ed technical personnel. Contact Murata Power Solutions if there is any doubt regarding installation and/or operation. 1. Measurement Type: All DMU-30DCV series dc voltmeters achieve their excellent performance by employing a precision integrating analog-to-digital converter, metal lm resistor dividers, and a high-stability voltage reference IC. The LED display is updated approximately 2.5 to 3 times per second. However, while some input ltering is provided, noisy signals may cause the displayed reading to vary by a few counts. 2. Wiring: All ac supply (TB1) and input signal (TB2) wiring must be adequately rated for CAL BRIGHTNESS ADJUST the voltages and currents they will carry, and must comply with any code or application- mandated requirements pertaining to the users speci c installation. 3. Power Supply Polarity, Fusing, Wiring and Grounding: The power supply inputs (TB1-1 and TB1-2) on DMU-30DCV voltmeters are not polarity sensitive, that is, they have no AC LO or AC HI designations. These units do not include or require a connection to earth/chas- 1 2 1 2 sis ground. Refer to Figure 1 for a typical wiring diagram. TB1 TB2 + Wires speci ed in the Functional Speci cations section must be used for making connec- tions to DMU-30DCV series voltmeters. All power-supply and load wiring must be rated REAR VIEW for the supply voltages and currents they will conduct and must comply with any code or application-mandated requirements pertaining to the users speci c installation. 85-264Vac Input Signal Power Source DMU-30DCV voltmeters are not internally fused. Terminal block TB1 is to be used only Figure 1. DMU-30DCV wiring diagram for powering the power meters internal circuitry it must not be used to supply power to external loads. The supply wires feeding these power meters must be fused with a 0.5A/250V time delay/time lag fuse, in accordance with applicable regulatory codes. Wire insulation must be stripped to within 10% of the stated dimensions, and wires should be inserted into TB1 such that their insulation is not pinched by the screw terminal. For full details go to www.murata-ps.com/rohs www.murata-ps.com/support MPM DMU 30DCV.B01 Page 1 of 3DMU-30DCV Series Ruggedized DC Voltmeters with Daylight Readable Auto-Dimming LED Displays Performance/Functional Speci cations TECHNICAL NOTES (continued) Typical at TA = +25C, unless otherwise noted. 4. Calibration: Periodic recalibration of DMU-30DCV voltmeters is not required Input (TB2) Min. Typ. Max. Units under normal indoor operating environments. However, operation in environ- Full Scale Input Range: ments subject to vibration and/or extreme temperature variations should DMU-30DCV-0-DR-C 0 199.9 mVdc have their accuracy veri ed on a yearly basis. If recalibration is necessary, DMU-30DCV-1-DR-C 0 1.999 Vdc it should only be performed by quali ed technical personnel. Calibration is performed with potentially lethal voltages applied to the DMU-30DCV and its DMU-30DCV-2-DR-C 0 19.99 Vdc associated wiring. A plastic, fully-insulated adjusting tool must be used to DMU-30DCV-3-DR-C 0 199.9 Vdc access the recessed calibration potentiometer located on the back of the unit Performance (see Mechanical Speci cations). Contact Murata Power Solutions if additional Sampling Rate 2.5 readings per second information is required regarding calibration, setup, or any other technical Accuracy 0.4%FS 2 counts issue pertaining to DMU-30DCV dc voltmeters. Zero Reading (within 30 sec.) 001 000 001 Cnts 5. Minimum-Intensity Adjustment Potentiometer: Users can adjust the Temperature Drift (0 to +60C) 0.2 0.4 Cnts/C DMU-30DCVs minimum LED display brightness to suit their indoor viewing Breakdown Voltage (TB1 to TB2) 2000 Vdc requirements by adjusting the -turn, rear-mounted intensity adjustment potentiometer. Please note, this potentiometer will have minimal impact on Supply Voltage (TB1) display brightness in high ambient light environments. DMU-30DCV 85 264 Vac/47- 63Hz The intensity adjustment potentiometer is factory preset to its mid-point po- sition. As viewed from the rear of the meter, and with the model number label Supply Current (TB1) facing up, turning the potentiometer clockwise increases the LED displays DMU-30DCV (total darkness) 4 6 mA/47- intensity. See the Mechanical Speci cations section for potentiometer loca- 63Hz tions. DMU-30DCV (full sunlight) 40 50 mA/47- 63Hz 6. Operation with Power Supplies Lower than 85Vac: In indoor applications Terminal Block Wiring (TB1 & TB2) where daylight readability (i.e., maximum display brightness) is not required, DMU-30DCV meters will meet their speci ed accuracy with ac supply volt- Wire Size 16-22 AWG, Solid or stranded ages (TB1) well below 85Vac. While performance is not guaranteed, DMU- Insulation Strip Length 0.250 inches (6.35) 30DCV voltmeters remain easily readable and accurate with ac supplies as Screw Tightening Torque 2.2 lbin (0.25 Nm) 20% low as 20Vac. Rated Voltage 300Vac 7. Panel Installation: All electrical connections to DMU-30DCV must be made Display after the meter is securely attached to the panel and with all input and Display Type and Size Daylight readable, auto-dimming, supply voltages de-energized (off). Care must be exercised when attach- 3 digit, 0.56 /14.2mm high red LED ing conductors to terminal blocks TB1 and TB2. The installed wire-positions Decimal Point Fixed, model dependent should be such that minimal forces are applied to the terminal blocks or the Overrange Indication1 voltmeter. In high-vibration environments, adequate strain reliefs must be used on all input and supply wiring. Physical/Environmental Operating Temperature 25 +60 C To ensure a secure and moisture/vibration resistant installation, use only the supplied hardware. Following the four-step sequence shownbeing Storage Temperature 40 +75 C careful not to apply excessive force or twisting motionsinsert the voltmeter Humidity (non-condensing) 0 85 % into the panel opening. Tighten all six M3 metric screws to 3 inch-pounds Dimensions See mechanical speci cations (0.34Nm). See the Mechanical Speci cations section for panel cutout, drill Weight 1.3 ounces (36 grams) nominal dimensions, and panel installation information. Display reading is set to 1888. Speci ed power supply currents are steady state larger Ordering Information surge currents can occur at initial application of ac power. Power supply input (TB1) set to 120Vac/60 Hz. Model Input Range DMU-30DCV-0-DR-C 0 to 199.9mVdc DMU-30DCV-1-DR-C 0 to 1.999Vdc DMU-30DCV-2-DR-C 0 to 19.99Vdc DMU-30DCV-3-DR-C 0 to 199.9Vdc See www.murata-ps.com/dpm-availability for model-speci c availability. www.murata-ps.com/support MPM DMU 30DCV.B01 Page 2 of 3