DCA5-20PC-1-DC1-RL-C - DATEL

Murata Power Solution’s new DCA5-20PC Series dc ammeters are speciﬁ cally designed to dis-

play the output of all popular 50mV and 100mV dc-shunts. 25 input ranges provide for precision

measurement of dc currents from 1.000A to 2000A. With the exception of an external shunt,

the unit is 100% self-contained – no calibration or user-supplied components are required.

Available LED-display colors include brilliant blue, bright green, and standard red. Three power

supply options accommodate all popular dc-supply voltages from 5V to 75Vdc, making these

ammeters perfect for automotive, industrial, telecom, and marine applications!

DCA5-20PC Series ammeters are housed in 1.38” x 0.88” (35mm x 22mm) rugged pack-

ages that feature a large, 0.37”/9.4mm high, LED display. However, display visibility is not com-

promised in any way: the display can be easily read at distances up to 15 feet (5 meters). All

input and power supply connections are made by way of two screw-style terminal blocks. For

added ﬂ exibility, computer-style jumpers are provided for range-speciﬁ c decimal point assign-

ments. And, to ensure trouble free installation, all models include reverse-polarity protected

power supply inputs.

Two input conﬁ gurations are offered: grounded shunt (“low-side”), 5-40V-powered, red,

green or blue LED models for cost-sensitive applications, and 8-36V isolated-supply models

that accept high-side or ﬂ oating shunts. Isolated-supply models are also available in a choice

of red, green, or blue LEDs. Since many dc ammeters are used in battery backup applications,

power consumption for 8-36V models is typically 1 Watt, and 75mW for 5-40V models.

Miniature size, wide supply inputs, and no-hassles installation make DCA5-20PC Series

ammeters the ideal choice for all your 50 and 100mV shunt ammeter-applications.

Figure 1. DCA5-20PC Series Simpliﬁ ed Schematic

A/D

CONVERTER

LED DISPLAY

INPUT

AMPLIFIER

EXTERNAL DC SUPPLY

POWER

CONVERTER

TB1

CAL

–5V

+5V

TB2

POWER

GROUND

SIGNAL

GROUND

EXTERNAL

50 or 100mV SHUNT

Not included on all models

Open on isolated power models

–V (GND)

+IN

–

–IN

–

12 12

FEATURES

 Scales and displays the output of 5A to

2000A, 50mV & 100mV shunts

 Completely self-contained – no additional

components required

 Wide power supply inputs: 5 to 40Vdc for

12V/24V/28V applications

 48V option for telecom supplies

 Isolated-supply models for high-side shunts

 Large, easy-to-read LED display with 0.37”

(9.4mm) high digits

 Available in red, blue or green LED displays

 Subminiature 1.38” x 0.88” package with

screw-style terminal blocks

 Factory calibrated to ±0.1% accuracy;

Reverse-polarity protection

 Over 50 models available

 Digital upgrade for analog meters

For full details go to

www.murata-ps.com/rohs

www.murata-ps.com

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DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 1 of 6

➀ A full-scale input voltage of 50.00mV is used to calibrate all models for their designated

measurement range. The ammeter’s rear calibration potentiometer compensates for

full-scale input variations up to ±1% (49.5 to 50.5mV).

Measuring positive and negative currents (bipolar operation): In applications

where both positive and negative currents must be measured, Murata Power Solu-

tions recommends using ‘-DC4’ 8-36V isolated supply models. Negative current

ﬂ ow is denoted by the illumination of the display’s negative (–) sign; the absence of

a negative sign implies positive current ﬂ ow. Contact MPS if you have any questions

regarding bipolar operation of DCA5-20PC ammeters.

➁ On non-isolated ‘-DC1’ models, continuous application of single-ended ±400mV

inputs will not damage the ammeter. Single-ended inputs are deﬁ ned as those

whose TB1-1 (–IN) potential is within ±0.1V of the potential on TB2-2 (-V). For

all models, the application of short-duration (5 seconds max.) ±1V inputs will not

damage the ammeter.

➂ Breakdown (isolation) voltage applies only to ‘-DC4’ isolated-power models.

Breakdown voltage is tested with TB1-1 tied to TB1-2 (–IN shorted to +IN) and

TB2-1 tied to TB2-2 (+V shorted to -V). 500Vdc is then applied between the

two shorted terminal-block pairs; the max. allowable leakage current is 5uA.

➃ Zero reading is measured with TB1-1 (–IN) shorted to TB1-2 (+IN).

➄ Power supply currents noted are measured with the 50mV shunt input (TB1) at

zero volts (display reads “000”) and one decimal point enabled.

➅ Each model’s full-scale display reading with a 50.0mV input is designated by the

ﬁ rst X in the DCA5-20PC-X-XXX model number structure. Decimal point selection

(DP1, DP2, DP3, or none) is performed by the user to suit desired amperage range.

Input ranges -1, -2, -3, -4, -7, -8 and -9 can accommodate 100mV shunts. For these

ranges, the indicated 50mV reading is doubled when a 100mV input is applied.

Performance/Functional Speciﬁ cations

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

DCA5-20PC - x - DC1 - RL - C

Power Supply:

DC1 = +5-40Vdc, non-isolated power

(available with -RL, -BL, or -PGL LEDs)

DC4 = +8-36Vdc, isolated power

(available with -RL, -BS, or -GS LEDs)

LED Color:

BL = Low-Power Blue

BS = Super Blue

GS = Standard Green

PGL = Low-Power Green

RL = Low-Power Red

Accessories:

DMS-20-CP Panel Cutout Punch

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

Shunt Model Rating Use with

3020-01097-0 5A/50mV DCA5-20PC-1

3020-01107-0 10A/100mV DCA5-20PC-1

3020-01098-0 20A/50mV DCA5-20PC-6

3020-01096-0 50A/50mV DCA5-20PC-1

3020-01099-0 100A/50mV DCA5-20PC-2

3020-01108-0 100A/100mV DCA5-20PC-1

3020-01100-0 150A/50mV DCA5-20PC-5

3020-01101-0 200A/50mV DCA5-20PC-6

3020-01102-0 300A/50mV DCA5-20PC-3

3020-01103-0 500A/50mV DCA5-20PC-1

3020-01104-0 800A/50mV DCA5-20PC-10

3020-01105-0 1000A/50mV DCA5-20PC-2

3020-01106-0 1200A/50mV DCA5-20PC-11

Input (TB1) ➀Min. Typ. Max. Units

Full Scale Input ➀49.5 50 50.5 mV

Overvoltage Rating ➁±400 – – mV

Input Impedance – 1K – Ohms

Shunt Input to Power Supply Isolation ➂

DCA-20PC-X-DC4 models only 500 – – Vdc

Performance

Sampling Rate 2.5 reading per second

Accuracy ±0.15%FS

Zero-Current Reading ➃“–001” “000” “001” Counts

Temperature Drift (0 = +60°C) – ±0.2 ±0.4 Cnts/°C

Power Supply Voltage (TB2)

DCA-20PC-X-DC1-XX +5.0 – +40 Vdc

DCA-20PC-X-DC4-XX +8 – +36 Vdc

Power Supply Current ➄

DCA-20PC-X-DC1-XX (@ 5-40V) – 10 15 mAdc

DCA-20PC-X-DC4-XX (@ 8V) – 100 150 mAdc

DCA-20PC-X-DC4-XX (@ 36V) – 25 40 mAdc

TB1 and TB2 Terminal Blocks

Wire Size 16-22AWG, solid or stranded

Insulation Strip Length 0.250 inches

Screw Tightening Torque 2.2 lb·in (0.25 N·m) ±20%

Rated Current 20A with 12AWG solid copper wire;

15A with 14AWG solid or stranded

copper wire

Display

Display Type and Size 3½ digit, 0.37"/9.4mm high red, blue or

green LED

Overrange Indication "–1_ _ _" for negative Vin

"1_ _ _" for positive Vin

Display Reading/Decimal Point Model dependent

Physical/Environmental

Operating Temperature 0 – +60 °C

Storage Temperature –20 – +75 °C

Humidity (non-condensing) 0 – 85 %

Case Material Polycarbonate

Dimensions 1.38"W x 0.88" x 1.0" nominal

Weight 0.6 ounces (17 grams)

Ordering Information

Add -C for RoHS

Use with these 50mV shunts* or with these 100mV shunts*

1 5A 50A 500A 10A 100A 1000A

2 1A 10A 100A 1000A 2A 20A 200A 2000A

3 30A 300A 60A 600A

4 75A 750A 15A 150A 1500A

5 15A 150A 1500A —

6 2A 20A 200A 2000A —

7 25A 250A 5A 50A 500A

8 400A 80A 800A

9 600A 120A 1200A

10 80A 800A —

11 1200A —

*With respective decimal point user enabled. See technical note 7.

Input Range:

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DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 2 of 6

–IN

–

+IN

–V

LOAD

50mV SHUNT

DC SUPPLY

5-40Vdc

POWER

GROUND

(0Vdc)

LOAD CURRENT

J3 MUST BE INSTALLED

(FACTORY SETTING) FOR

5-40Vdc SUPPLIES

J1 AND J2 POSITIONS

DEPEND ON INPUT RANGE

DCA5-20PC-X-DC1-XX

SHUNT MUST

BE IN LOW SIDE

1122

CAL

TB1 TB2

J1 J2

J3 11

1122

CAL

TB1 TB2

J1 J2J3 11

–IN

–

+IN

–V

LOAD

50mV SHUNT

DC SUPPLY

36-75Vdc

POWER

GROUND

(0Vdc)

LOAD CURRENT

REMOVE J3

FOR 36-75Vdc

SUPPLIES

SHUNT MUST

BE IN LOW SIDE

DCA5-20PC-X-DC1-XX

TECHNICAL NOTES

Figure 2. Low-Side Shunt Connections for "-DC1"

5-40Vdc Non-Isolated Supply Models

To ensure safe and reliable operation, DCA5-20PC dc ammeters must

only be installed and serviced by qualiﬁ ed technical personnel. DC

ammeter applications can expose a user to potentially lethal currents

and voltages. Power and signal connections must be made with all

associated power sources de-energized. Contact DATEL if you have any

questions regarding the installation or operation of any of our digital

instruments.

1. Calibration: DCA5-20PC ammeters are designed to operate with 50mV

and 100mV dc shunts whose rated accuracy is ±0.25%, or better. The

output of less accurate shunts may fall outside the ammeter’s ±1% calibra-

tion adjustment range. Under normal indoor operating conditions, periodic

recalibration of DCA5-20PC ammeters is not necessary. The calibration

potentiometer, located on the back of the ammeter, is a ¾ turn type; do not

force its adjustment screw past the two end stops.

If user calibration is deemed necessary, it must be performed by qualiﬁ ed

personnel. Calibration is performed by applying a precision 50.00mVdc or

100mVdc (model speciﬁ c, see ordering guide) signal to TB1, observing

correct polarity. Then, using an insulated slotted tool, adjust the calibration

potentiometer until the correct display reading is achieved. Contact MPS if

additional information is required regarding calibration or setup of DCA5-

20PC ammeters.

2. Wiring and Fusing: Power supply (TB2) and input (TB1) wiring must

be rated for the electrical and environmental conditions under which the

ammeters will be operated. They must also comply with any regulatory or

application-mandated requirements pertaining to the user’s installation. Con-

nections to DCA5-20PC ammeters must be made with all power sources

de-energized. Refer to the Functional Speciﬁ cations section for TB1 and

TB2 wire gauge information.

DCA5-20PC ammeters’ shunt (TB1) and power supply inputs (TB2) are not

internally fused. Therefore, the supply wires connected to the meter and the

load should be fused according to the maximum current rating (or lower)

of the wire gauge used, in accordance with applicable regulatory codes.

Insulation should be stripped to within +/-10% of the stated dimensions. All

wires must be inserted into the terminal block openings such that the screw

terminal does not pinch any insulation. TB2 is to be used solely for power-

ing the meter’s internal circuitry; it must not be used to supply current to an

external load or auxiliary device.

3. Terminal Block Torque Ratings: It is important to tighten TB1’s and TB2’s

screw-terminals to their rated torque speciﬁ cations of 3.6 pound-inches (0.4Nm).

Proper tightening will minimize losses and ensure reliable operation.

4. High-Side versus Low-Side Shunts: Incorrect shunt connections are

one of the most common problems encountered when applying digital

dc-ammeters. Incorrect shunt connections can cause permanent damage to

the ammeter and/or its associated equipment.

Low-Side Shunts: Applications that employ a single power supply to power both

the load and the ammeter, and the external shunt is located in the negative side

of the supply (commonly referred to as “low side” or “grounded shunt”) should

use ‘-DC1’ non-isolated power DCA5-20PC Series ammeters. Figures 2, 3, and 4

depict typical low-side shunt connections.

High-Side Shunts: ‘-DC4’ isolated-power ammeters must be used in all

applications that employ a single power supply to power both the load and

the ammeter and the shunt is located in the high side (positive terminal) of

the supply. Figures 5 and 6 depict typical high-side shunt connections. As

shown in Figure 6, isolated-power models can also be used in applications

Figure 3. Low-Side Shunt Connections for "-DC1" Models Modiﬁ ed for

36-75Vdc Non-Isolated Power (See Technical Note 5)

where one supply powers the ammeter and a second supply powers the

load, but the two supply grounds cannot be tied together. ‘-DC4’ isolated-

supply models include a built-in dc/dc converter to provide a minimum of

500Vdc isolation between the shunt (TB1) and power supply inputs (TB2).

5. Operation With 36 to 75Vdc Power: As shipped, all ‘-DC1’ models’ rated

operating supply range is +5 to +40Vdc. However, ‘-DC1’ models can be

user conﬁ gured for 36 to 75Vdc operation by removing (opening) jumper

J3. Please note that this user modiﬁ cation can only be performed on ‘-DC1

power models. Also, all ‘-DC1’ models – including those that have been

modiﬁ ed for 36-75Vdc operation – can only be connected in low-side,

grounded-shunt applications. See Figure 3 for detailed wiring information.

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DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 3 of 6

APPLICATIONS

Any reconﬁ guration of J3 must be made prior to connecting the power

supply and shunt to the ammeter.

6. Replacing Analog Panel Meters: DCA5-20PC ammeters can be

used as replacements for analog panel meters that are driven by

50 or 100mV shunts, if a suitable dc voltage is available for powering the

ammeter. In retroﬁ t applications, it is extremely important to determine the

shunt’s electrical conﬁ guration (i.e., high or low side). If any doubt exists as

to the shunt’s location, use only ‘-DC4’ isolated-supply models. Rewiring

must be performed with all power sources de-energized.

Figure 5. High-Side Shunt Connections for "-DC4"

8-36Vdc Isolated-Power Models

1122

CAL

TB1 TB2

J3 J1 J2

–IN

–

+IN

–V

LOAD

50mV SHUNT

DC SUPPLY

8-36Vdc

POWER

GROUND

(0Vdc)

LOAD CURRENT

Figure 4. Typical Low-Side Shunt Connections for "-DC1" Models

Measuring a Battery’s Charge/Discharge Current

1122

CAL

TB1 TB2

J1 J2

J3 11

LOADS

SOLAR

PANELS

CHARGE

DISCHARGE

50mV SHUNT

12 V

BATTERY

–IN

–

+IN

–+

–V

J3 MUST BE INSTALLED

(FACTORY SETTING) FOR

5-40Vdc SUPPLIES

J1 AND J2 POSITIONS

DEPEND ON INPUT RANGE

DCA5-20PC-X-DC1-XX

Figure 6. Using "-DC4" Isolated-Power Models to Maintain Isolation

Between Two Power Supplies

1122

CAL

TB1 TB2

J1J3 J2

–IN –

–

+IN +

–V

50mV SHUNT

LOAD CURRENT

DC SUPPLY #1

8-36Vdc

DC SUPPLY

LOAD

SHUNT CAN BE IN

LOW OR HIGH SIDE

Figure 7. Decimal Point Selection Using J2 and J1

(Applies to All Models)

1 1 2 2

CAL

TB1 TB2

J1 J2 J3 1 1

2 2

J2 CONFIGURATION

DP2 OFF

DP3 OFF

DP2 ON

(1X.XX)

DP3 ON

(1XX.X)

SG3

SG2

SG1

DP1 OFF

DP1 ON

(1.XXX)

J1 CONFIGURATION

ALL MODELS

7. Decimal Point Selection: As shown in the Ordering Information guide, DCA5-

20PC ammeters are multiple input-range devices. For example, with a 50mV

input, DCA5-20PC-1-DC1 models can be conﬁ gured to display “5.00”, “50.0, or

“500” Amps by simply removing or relocating decimal-point-selector jumper J2

(see Figure 7). Decimal points serve as placeholders only; they have no affect

on displayed accuracy or resolution. If jumper J2 is not available, solder gaps

SG1, SG2, or SG3 can be used to select DP1 (“1.XXX”), DP2 (“1X.XX”), or

DP3 (“1XX.X”), respectively.

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DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 4 of 6

APPLICATIONS

PANEL INSTALLATION

Step 1. Step 2. Step 3. Step 4.

8. Operation With 100mV Shunts: Many DCA5-20PC Series ammeters

can also operate with 100mV shunts. This is due to the fact that when

they are driven by a 100mV input, the display readings are double

those of a 50mV input. However, a 50mV shunt cannot be used in

a 100mV application because its maximum current rating will be

exceeded.

For our customer’s convenience, DATEL offers a series of 50mV and

100mV chassis-mount dc shunts that can be used with DCA5-20PC

ammeters. Part numbers for accessory shunts can be found in the

Ordering Information section. A data sheet describing these shunts is

available at www.datel.com.

Table 1 indicates the obtainable readings of the seven DCA5-20PC

models that can be operated with 100mV shunts. Be sure to enable the

correct decimal point (see decimal point selection instructions).

9. Noisy Power Supplies: Some power supplies contain high-frequency

switching devices that may conduct and/or radiate signiﬁ cant noise

onto the low-level 50/100mV shunt signal. Even though the DCA5-

20PC incorporates built-in ﬁ ltering at its shunt input, some portion of

this noise may be ampliﬁ ed and subsequently measured by the DCA5-

All connections and modiﬁ cations must be made after the ammeter

is securely attached to the panel, with all load and supply voltages

de-energized (off).

The installed wire-positions should be such that minimal forces are applied

to TB1, TB2, and the ammeter itself. In high-vibration environments, the

use of wiring strain-reliefs is recommended.

To insure a secure panel-mount installation, MPS recommends using the

DMS-BZL4-C (with sealing gasket) bezel assembly supplied with each

20PC’s sensitive circuitry. The ampliﬁ ed noise introduces errors that are

particularly noticeable at zero load current (i.e., the ammeter may not

display a relatively steady “000” reading).

Connecting an external, unpolarized capacitor across TB1’s “+” and

“–” inputs, and/or across the shunt’s 50mV output terminals, can help

reduce noise-related display errors. In certain situations, the use of

twisted pair or shield wiring may be required. As a general rule, avoid

using excessively long leads between the ammeter and the shunt.

Figure 8. Panel Installation

ammeter. See the Mechanical Speciﬁ cations section for detailed panel

cutout and ammeter dimensions.

Following the four-step sequence shown in Figure 8 below, being careful

not to apply excessive force or twisting motions, insert the ammeter into

the panel opening. When using the DMS-BZL4-C’s sealing gasket, make

sure it is positioned between the ammeter’s ﬂ ange and the panel’s front

surface. Be sure to use and securely tighten all four screws supplied with

the bezel assembly.

Model 100mV Shunt Readings

DCA5-20PC-1 10.00A/100.0A/1000A

DCA5-20PC-2 1.999A/19.99A/199.9A/1999A

DCA5-20PC-3 60.0A/600A

DCA5-20PC-4 150.0A/1500A

DCA5-20PC-7 50.0A/500A

DCA5-20PC-8 800A

DCA5-20PC-9 1200A

Table 1. 100mV Shunt Readings *

* With respective decimal point enabled

1"/&- #&;&-

("4,&5

PQUJPOBM

1"/&- 1"/&- 1"/&-

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DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 5 of 6

#2-56 INSERT

0.156 (3.96) DEEP

FRONT VIEW

1.280

(32.51)

0.187

(4.75)

DMS-BZL4 BEZEL RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS

1.826 (46.38)

0.838

(21.29)

1.626 (41.30)

1.07

(27.18)

INTERNAL CORNER RADII:

0.032 (0.81) MAX.

0.093 (2.362) DIAMETER (4 REQUIRED)

ONLY WHEN USING SUPPLIED BEZEL ASSEMBLY

0.116 (2.95)

1.336 (33.93) 0.145 (3.68)

MECHANICAL DIMENSIONS: Inches (mm)

TOLERANCES: 2 PL DEC ±0.02 (±0.51)

3 PL DEC ±0.010 (±0.254)

1122

CAL

TB1 TB2

J1 J2J3

SG3

SG2

SG1

0.80

(20.3)

0.88

(22.4)

1.30

(33.0)

0.040

(1.02)

1.00

(25.4)

0.475

(12.1)

0.040

(1.02)

1.38

(35.1)

1.42

(36.1)

FRONT VIEW BACK VIEW

–IN

DP2DP1 DP3

+IN +V –V

MECHANICAL SPECIFICATIONS

BEZEL INSTALLATION AND RECOMMENDED DRILL AND PANEL CUTOUT

Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other

technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply

the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Speciﬁ cations are subject to change without

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Murata Power Solutions, Inc.

11 Cabot Boulevard, Mansﬁ eld, MA 02048-1151 U.S.A.

ISO 9001 and 14001 REGISTERED

DCA5-20PC Series

50mV & 100mV Input, LED-Display,

Subminiature DC Ammeters

MPM_DCA5-20PC.B09 Page 6 of 6