MURATA DMU

DMU-30DCV Series
www.murata-ps.com
Ruggedized DC Voltmeters with Daylight Readable
Auto-Dimming LED Displays
FEATURES
■
Measure and accurately display dc voltages in harsh
environments
■
Four input ranges: ±200mVdc, ±2Vdc, ±20Vdc, and
±200Vdc
■
Daylight-readable LED display with automatic
brightness adjustment
■
Moisture & impact resistant package offers
NEMA-4/IP65 protection
■
Operates from universal 85-264Vac mains, or
110-300Vdc supplies
■
Input circuit fully isolated from ac power supply
■
UL certification pending
Murata Power Solutions’ DATEL branded 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 installation, 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:
±200mVdc (with 0.1mV resolution); ±2Vdc (0.001V resolution); ±20Vdc (0.01V resolution);
and ±200Vdc (0.1V resolution). The dc signal under measurement is electrically isolated
from the unit’s operating power source.
DMU-30DCV series’ miniature size and rugged package are perfect for industrial and
high-reliability instrumentation, alternative power generators, and any other application
which requires daylight readability and precise monitoring of dc voltages in harsh indoor /
outdoor environments. Simply connect the input signal and an 85-264Vac source of operating power to the two rear-mounted terminal blocks and the unit is fully operational.
TECHNICAL NOTES
IMPORTANT! To ensure safe and reliable operation, DMU-30DCV dc voltmeters must
be installed and serviced by qualified technical personnel. Contact Murata / DATEL 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 film
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 filtering is provided,
noisy signals may cause the displayed reading to vary by a few counts.
CAL
1
2. Wiring: All ac supply (TB1) and input signal (TB2) wiring must be adequately rated for
the voltages and currents they will carry, and must comply with any code or applicationmandated requirements pertaining to the user’s specific installation.
BRIGHTNESS
ADJUST
2
1
2
TB1
TB2
DMU-30DCV dc voltmeters are not internally fused. If fusing is required, it must be externally user-provided according to the supply wire’s maximum amperage rating.
REAR VIEW
85-264Vac
Power Source
Input Signal
Figure 1. DMU-30DCV wiring diagram
For full details go to
www.murata-ps.com/rohs
3. Power Supply Polarity, Fusing, and Grounding: The operating-supply terminals (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/
chassis ground. Refer to Figure 1 for a typical wiring diagram.
4. Calibration: Periodic recalibration of DMU-30DCV voltmeters is not required under
normal indoor operating environments. However, operation in environments subject to
vibration and/or extreme temperature variations should have their accuracy verified
on a yearly basis. If recalibration is necessary, it should only be performed by qualified
technical personnel. Calibration is performed with potentially lethal voltages applied to
the DMU-30DCV and its associated wiring. A plastic, fully-insulated adjusting tool must be
used to access the recessed calibration potentiometer located on the back of the unit (see
Mechanical Specifications). Contact Murata / DATEL if additional information is required
regarding calibration, setup, or any other technical issue pertaining to DMU-30DCV dc
voltmeters.
Technical enquiries email: [email protected], tel: +1 508 339 3000
MPM_DMU_30DCV.A05 Page 1 of 3
DMU-30DCV Series
Ruggedized DC Voltmeters with Daylight Readable
Auto-Dimming LED Displays
Performance/Functional Specifications
TECHNICAL NOTES (continued)
Typical at TA = +25°C, unless otherwise noted.
5. Minimum-Intensity Adjustment Potentiometer: Users can adjust
the DMU-30DCV’s minimum LED display brightness to suit their indoor
viewing requirements by adjusting the ¾-turn, rear-mounted intensity
adjustment potentiometer. Please note, this potentiometer will have
minimal impact on display brightness in high ambient light environments.
The intensity adjustment potentiometer is factory preset to its midpoint position. As viewed from the rear of the meter, and with the
model number label facing up, turning the potentiometer clockwise
increases the LED display’s intensity. See the Mechanical Specifications section for potentiometer locations.
6. Operation with Power Supplies Lower than 85Vac: In indoor applications where daylight readability (i.e., maximum display brightness)
is not required, DMU-30DCV meters will meet their specified accuracy
with ac supply voltages (TB1) well below 85Vac. While performance is
not guaranteed, DMU-30DCV voltmeters’ remain easily readable and
accurate with ac supplies as low as 20Vac.
7. Panel Installation: All electrical connections to DMU-30DCV must
be made after the meter is securely attached to the panel and with all
input and supply voltages de-energized (off). Care must be exercised
when attaching conductors to terminal blocks TB1 and TB2. The
installed wire-positions should be such that minimal forces are applied
to the terminal blocks or the voltmeter. In high-vibration environments,
adequate strain reliefs must be used on all input and supply wiring.
To ensure a secure and moisture/vibration resistant installation,
use only the supplied hardware. Following the four-step sequence
shown—being careful not to apply excessive force or twisting
motions—insert the voltmeter into the panel opening. Tighten all six
M3 metric screws to 3 inch-pounds (0.34Nm). See the Mechanical
Specifications section for panel cutout, drill dimensions, and panel
installation information.
Min.
Typ.
Max.
Units
DMU-30DCV-0-DR-C
0
–
199.9
mVdc
DMU-30DCV-1-DR-C
0
–
1.999
Vdc
DMU-30DCV-2-DR-C
0
–
19.99
Vdc
DMU-30DCV-3-DR-C
0
–
199.9
Vdc
Input (TB2)
Full Scale Input Range:
Performance
Sampling Rate
2.5 readings per second
Accuracy
±0.4%FS ±2 counts
Zero Reading (within 30 sec.)
Temperature Drift (0 to +60°C)
Breakdown Voltage (TB1 to TB2)
“–001”
“000”
“001”
Cnts
–
±0.2
±0.4
Cnts/°C
2000
–
–
Vdc
Supply Voltage (TB1)
DMU-30DCV
85
–
264
Vac/4763Hz
DMU-30DCV (total darkness)
–
4
6
mA/4763Hz
DMU-30DCV (full sunlight)
–
40
50
mA/4763Hz
Supply Current (TB1) c
Terminal Block Wiring (TB1 & TB2)
Wire Size
16-22 AWG, Solid or stranded
Insulation Strip Length
0.250 inches (6.35)
Screw Tightening Torque
3.6 pound-inches (0.4Nm)
Rated Voltage
300Vac
Display
Display Type and Size
Daylight readable, auto-dimming,
3½ digit, 0.56"/14.2mm high red LED
Decimal Point
Fixed, model dependent
Overrange Indication
"1_ _ _ "
Physical/Environmental
–25
–
+60
°C
Storage Temperature
–40
–
+75
°C
0
–
85
%
Humidity (non-condensing)
Ordering Information
Model
DMU-30DCV-0-DR-C
DMU-30DCV-1-DR-C
DMU-30DCV-2-DR-C
DMU-30DCV-3-DR-C
Operating Temperature
Input Range
0 to ±199.9mVdc
0 to ±1.999Vdc
0 to ±19.99Vdc
0 to ±199.9Vdc
www.murata-ps.com
Dimensions
See mechanical specifications
Weight
1.3 ounces (36 grams) nominal
➀ Display reading is set to “1888”. Specified power supply currents are steady state; larger
surge currents can occur at initial application of ac power. Power supply input (TB1) set to
120Vac/60 Hz.
Technical enquiries email: [email protected], tel: +1 508 339 3000
MPM_DMU_30DCV.A05 Page 2 of 3
DMU-30DCV Series
Ruggedized DC Voltmeters with Daylight Readable
Auto-Dimming LED Displays
Mechanical Dimensions: Inches (mm)
Tolerances: 2 PL DEC ±0.02 (±0.51)
3 PL DEC ±0.010 (±0.254)
2.85
(72.39)
M3 INSERT
0.10 (2.54) DEPTH
1.5
(38.1)
1.60
(40.64)
CAL
BRIGHTNESS
ADJUST
1.97
(50.0)
0.26
(6.6)
1
2
1
TB1
TB2
PWR
SUPPLY
INPUT
FRONT VIEW
2
REAR VIEW
VIN
SIGNAL
INPUT
RECOMMENDED DRILL AND PANEL CUTOUT
2.118
(53.8)
Note: The supplied screws and
washers will accommodate
panel thicknesses from 0.060 to
0.090 inches (1.52 to 2.28 mm).
1.30
(33.02)
0.136 (3.45) DIA
(6 REQUIRED)
0.878
(22.3)
PANEL CUTOUT
INTERNAL CORNER RADII
0.032 (0.81) MAX.
1.26
(32.00)
2.52
(64.00)
PANEL INSTALLATION
Step 1.
Step 2.
Step 3.
Step 4.
USA:
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356
www.murata-ps.com email: [email protected] ISO 9001 and 14001 REGISTERED
03/18/09
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.
© 2009 Murata Power Solutions, Inc.
www.murata-ps.com
Mansfield (MA), Tel: (508) 339-3000, email: [email protected]
Canada:
Toronto, Tel: (866) 740-1232, email: [email protected]
UK:
Milton Keynes, Tel: +44 (0)1908 615232, email: [email protected]
France:
Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: [email protected]
Germany:
München, Tel: +49 (0)89-544334-0, email: [email protected]
Japan:
Tokyo, Tel: 3-3779-1031, email: [email protected]
Osaka, Tel: 6-6354-2025, email: [email protected]
China:
Shanghai, Tel: +86 215 027 3678, email: [email protected]
Guangzhou, Tel: +86 208 221 8066, email: [email protected]
Singapore:
Parkway Centre, Tel: +65 6348 9096, email: [email protected]
Technical enquiries email: [email protected], tel: +1 508 339 3000
MPM_DMU_30DCV.A05 Page 3 of 3