ACA-20PC Datasheet, PDF (1/6 Pages) Murata Power Solutions Inc. – Digital, LED-Display AC Ammeters with Built-in Current Transformers

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ACA-20PC Series
Digital, LED-Display AC Ammeters with
Built-in Current Transformers
FEATURES
■ Built-in Current Transformers for direct measurement
of 0 to 2/20/50/100 Amps
■ Functionally complete:
On-board current transformers
Scaling/interface circuitry
Precision A/D converters
Bright red LED displays
■ 8 different models
■ Subminiature, 1.38" x 0.88" package
■ Easy-to-read, 0.37"/9.4mm digits
■ AC powered models 85-264Vac @ 50/60Hz
■ "Self-powered" 85-264Vac, 2A and 20A models feature
built-in load connections
■ +5-40V dc powered models
■ 2000V isolation; UL/CSA recognized
SIMPLIFIED SCHEMATIC DIAGRAM
DATEL's new ACA-20PC Series are the first digital ac ammeters to incorporate on-board current
transformers (CT’s), and they are amazingly easy to use. Simply pass the current-carrying load
wire through the ACA-20PC’s on-board CT, apply power to the meter's two supply terminals,
and you’re instantly measuring ac currents over one of four ranges (0-2A with 1mA resolu-
tion, 0-20A with 10mA resolution, or 0-50A and 0-100A with 100mA resolution). Absolutely no
external components, such as expensive low-value shunts or 5A "donut" CT’s, are required.
Meters are ac powered (120/220Vac @ 50/60Hz) or dc powered (+5-40V) and impose
minimal loads (50mA max. and 120mA max., respectively) on their supplies. All models employ
auto-zeroing circuits, precision bandgap references, and super stable thin-film resistors for
unsurpassed accuracy (±0.15%FS) and stability.
The functionally complete ACA-20PC ammeters provide all the scaling/interface circuitry to
mate the CT’s output to a precision (3½ digit) A/D converter. The A/D's output goes directly to
drivers for the meters’ large (0.37"/9.4mm digit height), easy-to-read, LED displays. AC-pow-
ered units have on-board AC/DC converters, and wide-range dc-powered units have on-board
linear regulators. AC-powered models can be powered by the same ac supply whose current
they are monitoring. The 2A and 20A, 85-264Vac, 50/60Hz ("AC1") models feature additional
on-board terminal blocks to supply power to the external load. All models provide 2000Vdc iso-
lation between the measured ac current and their power supply, and all are UL/CSA recognized.
Each meter is housed in a subminiature, 1.38" x 0.88", epoxy-encapsulated package. Total
behind-the-panel installation depth is approximately 2 inches.
RMS-to-DC
CONVERTER
(L1)
CAL.
+
3½ DIGIT
A/D CONVERTER
–
+V
–V
POWER
CONVERTER
LED DISPLAY
BUILT-IN
CURRENT
TRANSFORMER
Ḥ
For full details go to
www.murata-ps.com/rohs
MEASURED AC
LOAD CURRENT
A
B
Figure 1. ACA-20PC Series simplified schematic
TB1
AC INPUT POWER
www.murata-ps.com
Technical enquiries email: [e-mail], tel: [phone]
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