DMS-20RM Series
True-rms ac Voltmeters with Isolated Inputs
FEATURES
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Measures the rms value of complex ac voltages
Three input ranges: 20Vac, 200Vac and 300Vac
Two operating-supply options: 85-264Vac, or +10-40Vdc
Input circuit fully isolated from operating power supply
47-1kHz input frequency range
Fully encapsulated plastic package measures 1.38” x
0.88” (35mm x 22.4mm)
Large, easy-to-read, red LED display is visible from 12
feet (4m)
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Murata Power Solutions’ DMS-20RM series are four-wire, self-contained ac voltmeters
that measure and display the true-rms values of complex ac waveforms. Because the input
circuitry is electrically isolated from the unit’s operating power source, these voltmeters
can measure signals down to zero volts. No external isolation transformers or auxiliary
power supply conditioning components are required. Simply connect the input signal and a
source of operating power (85-264Vac, or an optional +10-40Vdc) to the two rear-mounted
terminal blocks and the unit is fully operational.
DMS-20RM rms voltmeters are available in a choice of three input ranges: 20Vac
(with 0.01V resolution); 200Vac (0.1V resolution); and 0-300Vac (1V resolution). An input
frequency range of 47-1kHz makes these voltmeters ideal for all ac voltage monitoring
applications. And, unlike conventional, average-responding products, these meters can
measure and accurately display the true-rms value of triangle waves, square waves, or
other irregularly shaped waveforms with 0.4% full-scale accuracy.
The large (0.37”/9.4mm), bright red LED display makes the DMS-20RM ac voltmeters
easily readable from as far as 12 feet (4 meters). All units are packaged in a red-filter case
with a built-in bezel; these meters are fully encapsulated to make them moisture and vibra-
tion resistant. Their miniature size is perfect for high-end consumer electronics, laboratory
instrumentation, alternative power generators and other products requiring precise ac line
monitoring.
TYPICAL WIRING DIAGRAMS
AC POWER
SUPPLY
A
TB1
AC POWER
SUPPLY
+
-
A
B
10-40Vdc
DC POWER
SUPPLY
B
TB1
A
B
TB1
TB2
TB2
TB2
AC VOLTAGE
TO BE MEASURED
Figure 1B.
Powered by and measuring the same AC power source.
AC VOLTAGE
TO BE MEASURED
Figure 1A.
Powered by AC supply while measuring separate AC signal.
Figure 2.
Powered by DC power supply while measuring AC signal.
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com
Technical enquiries
email: sales@murata-ps.com, tel:
+1 508 339 3000
MPM_DMS-20RM.A02
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MURATA-PS [ MURATA POWER SOLUTIONS INC. ]
