DATEL ACA-20PC-4-DC3-RL, ACA-20PC-4-DC3-RH, ACA-20PC-4-DC3-GS, ACA-20PC-4-DC2-RL, ACA-20PC-4-DC1-RL Datasheet

DATEL, Inc., Mansfield, MA 02048 (USA) • Tel: [phone] Fax: [phone] • E–mail: [e-mail] • Internet: www.datel.com

ACA-20PC Series

Digital, LED-Display

AC Ammeters with Built-in

Current Transformers

Figure 1. ACA-20PC Series Simplified Schematic

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 or green LED displays

• 32 different models

• Subminiature, 1.38" x 0.88" package

• Easy-to-read, 0.37"/9.4mm digits

• AC powered models:

85-264Vac @ 50/60Hz
240-310Vac @ 50/60Hz
85-140Vac @ 400Hz

• "Self-powered" 85-264Vac, 2A and 20A

models feature built-in load connections

• DC powered models:

+5V, +5-40V, +36-75V

• 2000V isolation; UL/CSA recognized

AC or DC

INPUT POWER

POWER

CONVERTER

3½ DIGIT

A/D CONVERTER

+V –V

–

+

PRECISION

FULL-WAVE

RECTIFIER

CAL.

LED DISPLAY

BUILT-IN

CURRENT

TRANSFORMER

(L1)

TB1

A B

–+

MEASURED AC

LOAD CURRENT

Order on-line
at www.datel.com

E156931

DATEL's new ACA-20PC Series are the first digital ac ammeters to incorporate on­board 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 resolution, 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 (120/220/277Vac @ 50/60Hz or 120Vac @ 400Hz) or dc
powered (+5V, +5-40V, or +36-75V) 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-powered 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 isolation 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. Display color options
include standard red, high-intensity red, and standard green.

2

DATEL, Inc., Mansfield, MA 02048 (USA) • Tel: [phone] Fax: [phone] • E–mail: [e-mail] • Internet: www.datel.com

ACA-20PC Series

3½ DIGIT, LED DISPLAY, AC AMMETERS

Physical/Environmental
Dimensions 1.38"W x 0.88"H Depth is model

dependent (see Mechanical Specifications)

Weight:

ACA-20PC-1-XXX-XX 1.1 ounces (31 grams)
ACA-20PC-2-XXX-XX 1.1 ounces (31 grams)
ACA-20PC-3-XXX-XX 1.3 ounces (37 grams)
ACA-20PC-4-XXX-XX 1.5 ounces (43 grams)

Rated Full-Scale Current ➁ Min. Typ. Max. Units

ACA-20PC-1-XXX-XX — — 1.999 Amps
ACA-20PC-2-XXX-XX ➂ — — 19.99 Amps
ACA-20PC-3-XXX-XX — — 50.0 Amps
ACA-20PC-4-XXX-XX — — 100.0 Amps

Overcurrent Rating ➁ 1.5 x rated full-scale current
Performance
Sampling Rate 2.5 samples per second
Accuracy ➁ ±0.15%FS ±6 counts
Measurement Type Sine wave input, full-wave

averaging, rms calibrated

Temperature Drift (0 to +60°C) — ±0.2 ±0.4 Counts/°C
Zero-Current Reading –001 000 001 Counts
Dielectric Withstanding Voltage 2000 — — Vdc
Power Supply Voltage ➄

ACA-20PC-X-AC1-XX 85 120 264 Vac@47-99Hz
ACA-20PC-X-AC2-XX 85 120 140 Vac@350-450Hz
ACA-20PC-X-AC3-XX 240 264 310 Vac@47-99Hz
ACA-20PC-X-DC1-XX +4.75 — +40 Vdc
ACA-20PC-X-DC2-XX +36 — +75 Vdc
ACA-20PC-X-DC3-XX +4.75 — +5.25 Vdc

Power Supply Current ➃

ACA-20PC-X-AC1,3-XX — 30 50 mA@47-99Hz
ACA-20PC-X-AC2-XX — 30 50 mA@350-450Hz
ACA-20PC-X-DC1,2-XX — +8 +12 mAdc
ACA-20PC-X-DC3-XX — +80 +120 mAdc

Power Supply Terminal Block
ACA-20PC-1-AC1-RL & ACA-20PC-2-AC1-RL

(2A and 20A ac-powered models with 4-position terminal blocks):

Wire Size & Type 12-20AWG (solid), 14-20AWG (stranded)
Insulation Strip Length 0.25 inches
Screw Tightening Torque 4.4 pound-inches (0.5Nm)
Maximum Rated Current 20A with 12AWG solid wire;

15A with 14AWG solid or stranded wire

Maximum Rated Voltage 630V (VDE 0110-V. Group 2);

250V (VDE 0110-V. Group 3)

ACA-20PC-X-XXX-XX

(All other ac/dc-powered models with 2-position terminal blocks):

Wire Size & Type 16-24AWG (solid or stranded)
Insulation Strip length 0.25 inches
Screw Tightening Torque 3.6 pound-inches (0.4Nm)
Maximum Rated Voltage 310Vac

Display
Display Type and Size 3½ digit LED, 0.37”/9.4mm digit height
Overrange Indication "1___"
Decimal Point Fixed, model dependent
Physical/Environmental
Operating Temperature 0 — +60 °C
Storage Temperature –40 — +75 °C
Humidity (non-condensing) 0 — 95 %
Case Material Polycarbonate

➀ The ACA-20PC-1-AC1-RL and ACA-20PC-2-AC1-RL have 4-position on-board terminal

blocks. All other models have 2-position terminal blocks.

➁ Specified full-scale currents are those passing through the built-in CT's primary (load) circuit,

over the frequency of 45-450Hz. The Overcurrent Rating is a continuous rating that applies to
the measured ac load current. It does not apply to any circuitry external to the meter.
Accuracy is guaranteed to the rated current.

➁ For the ACA-20PC-2-AC1-RL, if the load is connected to the meter's on-board 4-position

terminal block, the 20A full scale range requires 12AWG solid copper wire on all connections.
If 14AWG solid copper wire is used, the current should be limited to 15A. See Figure 3.

➃ All specified maximum power supply currents are steady-state values. AC-powered models

can draw higher surges at initial turn-on.

➄ Maximum reverse polarity protection on "DC1" models is –40Vdc, and –50Vdc on "DC2"

models. "DC3" models provide no reverse polarity protection.

Performance/Functional Specifications

Typical at TA = +25°C, unless otherwise noted. ➀

IMPORTANT! To ensure safe and reliable operation, ACA­20PC ammeters must be installed and serviced by qualified
technical personnel. Contact DATEL if there is any doubt
regarding ammeter installation and/or operation.

1. Measurement Type: ACA-20PC ac ammeters employ a full-wave-

rectified, average responding, rms-calibrated circuit to measure the
stepped-down output of their on-board, L1 current transformer (CT) .
Stated accuracy specifications are measured using a sine-wave
current at or close to the specified full scale input level, at nominal line
frequency.

2. Calibration: Periodic recalibration of ACA-20PC ammeters is not
required under normal, indoor operating environments. If user
calibration is necessary, it should be performed by qualified technical
personnel. Calibration is performed with potentially lethal voltages
applied to the ACA-20PC and its associated wiring, with the specified
full-scale current flowing through the ammeter’s built-in current
transformer. A plastic, fully insulated adjusting tool must be used to

Technical Notes

Ordering Information

ACA - 20PC - 1 - AC1 - RL

1 = 1.999A
2 = 19.99A
3 = 50.0A
4 = 100.0A

RL = Red Standard
RH = High-Intensity Red*
GS = Green Standard*

AC1 = 85-264Vac@50/60Hz
AC2 = 85-140Vac@400Hz
AC3 = 240-310Vac@50/60Hz
DC1 = +5-40Vdc
DC2 = +36-75Vdc
DC3 = +5Vdc

Accessories: DMS-20-CP Panel cutout punch

Input Range:

LED Color:

Power Supply:

A DMS-BZL4 bezel assembly with sealing gasket is supplied with each ammeter.

*

Available on "DC3" +5V

powered models only