ACA5-20RM Series
True-rms-AC Ammeters with 5A CT Inputs
FEATURES
Scales and displays the true-rms output of 5A current
transformers
Accurately measure complex ac current waveforms
Perfect for measuring current in IT applications
Available in three input ranges: 0-100A, 0 to 200A,
or 0 to 500A
Functionally complete:
On-board, low-burden toroid sensor
Scaling/interface circuitry
Precision A/D converter
Reliable single-board construction
Easy-to-read, red LED display with 0.37"/9.4mm digits
Two AC power options: 85-140Vac & 170-264Vac
(50/60Hz)
2000V isolation between ac supply and external CT
Digital replacement for analog meters
Murata Power Solutions’ ACA5-20RM Series accept the output of external 5A current
transformers (CTs) and accurately display the true-rms value of complex, non-sinusoidal ac
currents up to 500A. Operation and setup is straightforward: simply pass the external 5A
CT’s secondary 0-5A output leads through the ACA5-20RM’s on-board toroid sensor, apply
ac power, and the ammeter is fully operational. All models are totally self-contained—other
than the external 5A CT, no other user-supplied components are required.
Three input ranges measure 0-100.0 amps (with 0.1A resolution), 0-200 amps (0.1A
resolution), and 0-500 amps (1A resolution). Two power supply options are available:
85-140V (47-63Hz), and 170-264V (47-63Hz). Power consumption 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.
ACA5-20RM Series rms ammeters feature full-size, 0.37" (9.4mm) high, 3�½ digit,
bright red LED-displays and a built-in bezel/filter assembly that features metal fasteners.
They are also panel-cutout compatible with Murata Power Solutions’ DMS-20RM Series
of rms-reading ac voltage monitors, making ACA5-20RM ammeters perfect replace-
ments for older, less reliable, analog voltmeters and ammeters in today’s sophisticated
instrumentation.
PRECISION
rms-to-DC
CONVERTER
BUILT-IN
TOROID
SENSOR
L1
A
B
TB1
For full details go to
www.murata-ps.com/rohs
Figure 1. ACA5-20RM Series simplified schematic
www.murata-ps.com
Technical enquiries
email: sales@murata-ps.com, tel:
+1 508 339 3000
MPM_ACA5-20RM.A01
Page 1 of 5
MURATA-PS [ MURATA POWER SOLUTIONS INC. ]
