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ACA-20RM Series

True-RMS-AC Ammeters with Built-in CT

For full details go to

www.murata-ps.com/rohs

www.murata-ps.com

Murata Power Solution’s new ACA-20RM Series are the world’s first digital ac-ammeters

to incorporate a built-in current transformer (CT) to directly measure the true-rms value of

complex, non-sinusoidal ac currents from 2 to 50A – no bulky and expensive 5A “donut”

CTs are required! Operation and setup is straightforward: simply pass the load-carrying

wire through the on-board CT, apply power, and the ammeter is fully operational.

Five input ranges measure 0-0.2 amps (0.1mA resolution), 0-2 amps (0.001A resolution),

0-20 amps (0.01A resolution), 0-30 amps (0.1A resolution) or 0-50 amps (0.1A resolution).

The 50A model features an oversized split-core current transformer that easily accommo-

(47-63Hz), and 170-264V (47-63Hz).

All models are totally self-contained; no external components are required. Power con-

sumption from a nominal 120V or 220V ac supply is less than 50mA. And, precision auto-

zeroing circuitry, super-stable components, and an rms-to-dc converter circuit combine to

achieve excellent performance when measuring the complex, non-sinusoidal, ac currents

found in today’s computer/telecom equipment.

ACA-20RM Series ammeters feature full-size, 0.37” (9.4mm) high, 3½ digit, bright red

LED-displays and a built-in bezel/filter assembly that features metal fasteners. They are

panel-cutout compatible with MPS’s DMS-20 Series of ac voltage and frequency monitors,

making ACA-20RM ammeters perfect replacements for older, less reliable, analog panel

meters in today’s sophisticated IT instrumentation.

FEATURES

Built-in CTs provide true-rms values of complex

waveforms

Perfect for measuring AC current in IT applications

Five ranges measure: 0-0.2A, 0-2A, 0-20A, 0-30A

and 0-50A

50A models features a split-core CT for easy installation

Self-powered from 85-140Vac or 170-264Vac

Large, easy-to-read, red LED display with 0.37” digits

Reliable single-board construction

Digital replacement for analog meters

UL and CSA recognized components

　

AC INPUT POWER

3½ DIGIT

A/D CONVERTER

+V

–V

–

+

RMS-to-DC

CONVERTER

CAL.

BUILT-IN

CURRENT

TRANSFORMER

LED DISPLAY

POWER

CONVERTER

TB1

AB

(L1)

MEASURED AC

LOAD CURRENT