DMS-20ACV Series www.murata-ps.com 480V, Self-Powered, AC Line Monitor FEATURES PRODUCT OVERVIEW Self-powered, 2-Wire operation Murata Power Solutions’ DMS-20ACV-3 is a low-cost, self-powered, 2-wire digital AC voltmeter designed for monitoring 3-phase, 480Vac primary ac power sources. The DMS-20ACV-3’s unique power-supply design allows a single model to operate from 350 to 600Vac, at line frequencies of 50 to 60Hz. No usersupplied external components or auxiliary power sources are needed for full operation. Its large, 0.40 inch (10.2mm), bright red or green LED display is easily readable under virtually all lighting conditions. DMS-20ACV-3 AC voltmeters employ a microprocessor driven, half-wave averaging, analog-to-digital converter to achieve a display resolution of 1Vac over its entire operating range. Also, the unit is permanently calibrated at the factory, ensuring stable, long-term accuracy by eliminating issues caused by user-accessible adjustment potentiometers. The DMS-20ACV-3 measures only 1.94” wide x 1.27” high (49.3mm x 32.3mm), and has an installed behind-the-panel depth of less than 1.0” (25.4mm). Panel mounting is greatly simplified by the use of a bezel assembly that includes a color filter and secure metal fasteners. This easy-to-use AC voltmeter is the ideal digital upgrade for fragile, less accurate, analog panel meters used in 480Vac power distribution environments. It similarly excels in any new application requiring accurate, high-voltage, AC line monitoring. Simply connect the AC power source to its 2-position terminal block and the unit is fully operational. 350 to 600Vac (50/60Hz) measurement range Digital replacement for analog panel meters Permanent, tamper-proof calibration Half-wave averaging, rms calibrated input Large, easy-to-read, bright red or green LED display Flashing display warns of overvoltage conditions Reliable screw-style terminal block simplifies hookup Rugged bezel assembly with secure metal fasteners Small footprint: 1.94W" x 1.27H" (49mm x 32mm) MECHANICAL SPECIFICATIONS FRONT VIEW SIDE VIEW 1.260 (32.00) 1.930 (49.02) BACK VIEW A 0.28 (7.1) 0.64 (16.3) MECHANICAL DIMENSIONS: Inches (mm) TOLERANCES: 2 PL DEC ±0.02 (±0.51) 3 PL DEC ±0.010 (±0.254) B TB1 For full details go to www.murata-ps.com/rohs www.murata-ps.com/support MPM_DMS-20ACV.A01.D4 Page 1 of 4 DMS-20ACV Series 480V, Self-Powered, AC Line Monitor TECHNICAL NOTES Performance/Functional Specifications IMPORTANT! To ensure safe and reliable operation, DMS-20ACV ac voltmeters must be installed and serviced by qualified technical personnel. Contact Murata Power Solutions if there is any doubt regarding installation and/or operation. Typical at TA=+ 25°C, 480Vac @ 60Hz, unless otherwise noted Input Supply Voltage (Vin @ TB1) Min. Typ. Max. Units AC (rms) Voltage @ 47-63Hz 350 480 600 Volts AC Performance Sampling Rate 2 Voltage Accuracy @ 25° C ±2 Temperature Drift (0 to 60ºC) 1. Measurement Type: DMS-20ACV series AC voltmeters employ a precision analog-to-digital converter and a stable voltage reference to measure and display the average value of sinusoidal AC mains voltages. Input voltages of 601V and above will cause the display to flash on and off. samples/sec ±4 Volts 0.05 Volts/°C Half-wave averaging, rms calibrated for sinusoidal inputs Measurement Type 2. Calibration: DMS-20ACV voltmeters are digitally calibrated at the factory; there is no provision for calibrating units in the field. Supply Current @ 50Hz 8 11 mA @ 60Hz 9 13 mA 3. Power Supply Polarity, Fusing, Wiring, and Grounding: DMS-20ACV-3’s TB1 ac-supply terminals are not polarity sensitive, that is, they have no “AC LO” or “AC HI” designations. These meters do not include nor require a connection to earth/chassis ground. Display Display Type 3 Digit LED Display Size 0.40 inches (10.16mm) high Overrange Indication DMS-20ACV-3 AC voltmeters are not internally fused. Terminal block TB1 is to be used only for powering the voltmeter’s internal circuitry; it must not be used to supply power to external loads or auxiliary devices. The supply wires connected to TB1 must be fused with a 0.25A/600V time delay/time lag fuse, in accordance with applicable regulatory codes. Flashing display for Vin > 600 Volts Physical/Environmental Weight 1.0 ounces (28 grams) Operating Temperature -25 60 °C Storage Temperature -40 75 °C 0 85 % Relative Humidity (Non Condensing) All AC-supply wiring must be rated for the voltages and currents they will conduct and comply with any code or application-mandated requirements pertaining to the user’s specific installation. 600V, ULrated wire suitable for the intended application is required. Ordering Information DMS-20ACV-3-R-C 350 to 600Vac (50/60Hz) Red LED Display DMS-20ACV-1-G-C 350 to 600Vac (50/60Hz) Green LED Display The recommended AC supply wire size is 16AWG to 22AWG (1.31mm2 to 0.325mm2) stranded copper wire. The supply wires must be properly stripped and attached to TB1 such that their insulation is not pinched by the screw terminal. Recommended insulation strip length is 0.25" (6.4mm). Rated tightening torque for the TB1’s screws is 7 poundinches (0.8 N-m). BACK VIEW Fuse* 0.25A/600V 350-600 Vac 47-63 Hz A B TB1 *See technical note 3. Figure 1. Wiring Diagram www.murata-ps.com/support MPM_DMS-20ACV.A01.D4 Page 2 of 4 DMS-20ACV Series 480V, Self-Powered, AC Line Monitor PANEL INSTALLATION All electrical connections to DMS-20ACV must be made after the voltmeter is securely attached to the panel, and with the input AC supply voltage de-energized (off). Care must be exercised when attaching the AC supply wires to terminal block TB1. The installed wire-positions should be such that minimal forces are applied to TB1 or the voltmeter. In high-vibration environments, adequate strain reliefs must be used on all supply wiring. Using Figure 2 as a guide, carefully insert the bezel/color filter assembly into the panel opening. From the rear of the panel, install the four 8mm plastic standoffs over the bezel’s threaded studs. Install the DMS-20ACV pc-board assembly and attach and tighten the four #2-56 hex nuts over the threaded studs. Tighten each hex nut to 15 to 20 ozf-in (0.11 to 0.14 N-m). Use only the factory-supplied hardware as the use of substitute hardware may result in an unsafe installation and/or adversely affect the reliability of the installation. The range of panel thicknesses that can be accommodated with the factory supplied hardware is 0.040 inches (1.0mm) to 0.125 inches (3.2mm). Panel thicknesses greater than 3.2mm may require additional user-supplied hardware or modifications to achieve an electrically safe and mechanically secure installation. However, do not use any substitutes for the 8mm round plastic standoffs supplied with the voltmeter. Please note, thick panels will alter the readability of the LED display. PANEL 0.032 (0.8) Thick Gasket Standoff Gasket Nut Standoff 0.315 (8mm) Board-Cutout Bezel DMS-20ACV AC Voltmeter SIDE VIEW Figure 2. Panel Installation BEZEL AND PANEL CUTOUT RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS 0.187 (4.75) 0.69 (17.5) FRONT VIEW 1.280 (32.51) INTERNAL CORNER RADII: 0.032 (0.81) MAX. 1.07 (27.18) 0.116 (2.95) 0.838 (21.29) 1.336 (33.93) 0.145 (3.68) 1.826 (46.38) 1.626 (41.30) 0.093 (2.362) DIAMETER (4 REQUIRED) www.murata-ps.com/support MPM_DMS-20ACV.A01.D4 Page 3 of 4 DMS-20ACV Series 480V, Self-Powered, AC Line Monitor NOTES Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. ISO 9001 and 14001 REGISTERED Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. © 2012 Murata Power Solutions, Inc. www.murata-ps.com/support MPM_DMS-20ACV.A01.D4 Page 4 of 4