ACA-20RM Datasheet, PDF (2/5 Pages) Murata Power Solutions Inc. – True-RMS-AC Ammeters with Built-in CT

Performance/Functional Specifications
Typical at TA = +25°C, unless otherwise noted.
Rated Full-Scale Current ~
ACA-20RM-O-ACX-RL
ACA-20RM-1-ACX-RL
ACA-20RM-2-ACX-RL
ACA-20RM-4-ACX-RL
ACA-20RM-5-ACX-RL
Overcurrent Rating 
Performance
Sampling Rate
Accuracy €
Measurement Type
Temperature Drift (0 to 60 °C)
Zero-Current Reading (within
30 sec.)
Dielectric Withstanding Voltage
Power Supply Voltage
ACA-20RM-X-AC3-RL
ACA-20RM-X-AC4-RL
Power Supply Current 
ACA-20RM-X-AC3-XX
ACA-20RM-X-AC4-XX
Power Supply Terminal Block
Wire Size
Insulation Strip Length
Screw Tightening Torque
Rated Voltage
Display
Display Type and Size
Overrange Indication
Decimal Point
Physical/Environmental
Operating Temperature
Storage Temperature
Humidity
Dimensions (non-condensing)
Weight
ACA-20RM-0,1,2-XXX-XX
ACA-20RM-4-XXX-XX
ACA-20RM-5-XXX-XX
Min. Typ. Max.
Units
–
– 199.9
mA
–
– 1.999
A
–
– 19.99
A
–
– 50.0
A
–
– 30.0
A
1.5 x Rated Full-Scale Current
2.5 Samples per second
±0.4%FS ±3 Counts with 60Hz
Sine-Wave Input
RMS Responding, Crest Factors of 1-5
– ±0.2 ±0.4 Cnts/°C
–001 000 001
Cnts
2000 –
–
Vdc
85 120
170 220
140 Vac/47-63Hz
264 Vac/47-63Hz
– 30 50 mA/47-63Hz
– 30 50 mA/47-63Hz
16-22AWG, Solid and stranded
0.250 inches
3.6 pounds-inches (0.4Nm)
310Vac
3½ Digit Red LED, 0.37”/9.4mm High
“1___”
Fixed, model dependent
(see full-scale input Current)
0
– +60
°C
–40 – +75
°C
–40 – +95
%
Model dependent, see page 3 & 4
1.1 ounces (31 grams) nominal
2.1 ounces (60 grams) nominal
1.5 ounces (43 grams) nominal
ACA-20RM Series
True-RMS-AC Ammeters with Built-in CT
~Specified full-scale currents are those passing through the ammeter’s built-in
current transformer’s primary load-circuit. See Notes 2 and 3 below for ad-
ditional model-specific information.
 The overcurrent rating of 1.5 x the rated full-scale current is a continuous rating
and applies to the current passing through the built in current transformer only,
it does not apply to any external circuit-wiring or external loads. Accuracy is
guaranteed up to the rated current level.
€ Specified accuracy applies to inputs with crest factors (CF) up to 2.0, where CF
= Vpeak/Vrms. Crest factors of 2 to 5 introduce an additional error of ±3% of full
scale. Ammeters are calibrated with a near full-scale 60Hz sine-wave current
flowing through the ammeter’s built-in CT.
 All specified maximum power supply currents are steady state; larger surge
currents can occur at initial application of line power.
Ordering Information
ACA-20RM- 1 - AC3 - R L - C
Add -C for RoHS
Input Range:
0 = 199.9mA
1 = 1.999A
LED Color:
Power:
RL = Low-Power Red
AC3 = 85-140Vac@50/60Hz
AC4 = 170-264Vac@50/60Hz
2 = 19.99A
4 = 50.0A (with split-core flying-lead CT)
5 = 30.0A (with flying-lead CT)
Accessories:
DMS-20-CP Panel Cutout Punch
TECHNICAL NOTES
IMPORTANT! To ensure safe and reliable operation, ACA-20RM
ammeters must be installed and serviced by qualified technical
personnel after reading this data sheet in it's entirety. Contact DATEL
if there is any doubt regarding their installation or
operation.
1. Measurement Type: ACA-20RM ac ammeters employ true-rms
input circuitry to measure the stepped-down output of their on-board
current transformers (CT). Stated accuracy is measured using a sine-
wave input at, or close to, the specified full scale input, at a nominal
line frequency of 60HZ.
2. Calibration: Periodic recalibration of ACA-20RM ammeters is not
required under normal indoor environments. If user calibration is
deemed necessary, it must be performed by qualified technical
personnel since potentially lethal voltages and currents are applied to
the ACA-20RM during the calibration process.
Calibration is performed with approximately 95% of the specified
full-scale current flowing through the ammeter’s built-in CT. A fully
insulated, non-metallic adjusting tool must be used to adjust the
calibration potentiometer, located on the back of the ammeter (see
Mechanical Specifications section).
www.murata-ps.com
Technical enquiries email: [e-mail], tel: [phone]
MPM_ACA-20RM_B02 Page 2 of 5