DCA-20PC Series www.murata-ps.com LED Display, Subminiature DC Ammeters with Built-In Shunts Murata Power Solutions new DCA-20PC Series are the rst digital dc ammeters to include built-in FEATURES shunts for measuring dc currents up to 20A. Six ranges provide for precision measurement of Built-in shunts for digitally measuring dc currents dc currents from 200uA to 20A. These ammeters are 100% self-contained no calibration or from 200uA to 20A user-supplied components are requiredthey even include terminal blocks for your external load circuit, a feature that enables simple 3-wire operation Functionally complete no additional components Two shunt-con gurations are offered: grounded-shunt (low side), 5-40V-powered models required for cost-sensitive applications, and 8-36V isolated-supply models for high side or oating shunt Wide power supply inputs: applications. A versatile power supply design accommodates all popular supply voltages from 5 to 5 to 40Vdc for 5V/12/24V/28V applications 75Vdc. Reverse-polarity-protected supply inputs ensure trouble free installation. And, because many 36-75V option for telecom supplies dc ammeters are installed in battery backup applications, power consumption is typically below 1 Watt for 8-36V models, and below 75mW for 5-40V models. To further reduce overall power con- 8-36Vdc Isolated-supply models for high-side shunts sumption, the voltage dropped across its built-in series shunt is only 20mV 20mV internal shunt minimizes power loss DCA-20PC Series ammeters are housed in subminiature, 1.38 x 0.88 (35mm x 22mm), Includes load connections for easy 3 or 4-wire rugged packages that feature a large, 0.37/9.4mm high, LED display. A built-in, high-contrast operation color lter ensures that legibility is not compromised: the display can be easily read at distances up to 15 feet (5 meters). Available LED-display colors include brilliant blue, bright green, and High resolution Factory calibrated to 0.1% accuracy standard red. Large, easy-to-read, LED display with 0.37 (9.4mm) Built-in shunts, Precision electronics, miniature size, wide power supply inputs, low power high digits consumption, and no-hassle 3-wire installation make DCA-20PC Series the ideal choice for all your 200uA to 20A ammeter-applications. Available with red, blue or green LED displays Small 1.38 x 0.88 x 1.0 package LED DISPLAY +5V INPUT A/D POWER AMPLIFIER CONVERTER CONVERTER + 5V BUILT-IN * POWER SHUNT GROUND SIGNAL + GROUND 1 1 2 2 3 2 12 Open on isolated-supply models TB2 TB1 * Applies to isolated-supply models only ** SHUNT +SHUNT LOAD (+) +V V ** (V) + EXTERNAL LOAD + EXTERNAL DC SUPPLY For full details go to www.murata-ps.com/rohs Figure 1. Simpli ed Schematic www.murata-ps.com/support MPM DCA-20PC.B07 Page 1 of 6DCA-20PC Series LED Display, Subminiature DC Ammeters Performance/Functional Speci cations Typical at TA = +25C, unless otherwise noted. with Built-In Shunts Full Scale Load Current Min. Typ. Max. Units Physical/Environmental (continued) DCA-20PC-1 199.9 Adc Humidity (non-condensing) 0 85 % DCA-20PC-2 1.999 mAdc Case Material Polycarbonate DCA-20PC-3 19.99 mAdc Dimensions 1.38 W x 0.88 x 1.0 nominal DCA-20PC-4 199.9 mAdc Weight 0.6 ounces (17 grams) DCA-20PC-5 1.999 Adc DCA-20PC-6 19.99 Adc Ordering Information Overcurrent Rating (<6 sec.) 1.5x rated full-scale load current Internal Shunt Resistance DCA-20PC - 1 - DC1 - R L - C DCA-20PC-1 100 Ohms Add -C for RoHS DCA-20PC-2 10 Ohms LED Color: DCA-20PC-3 1.0 Ohm BL = Low-Power Blue DCA-20PC-4 0.1 Ohm BS = Super Blue Input Range: GS = Standard Green DCA-20PC-5 0.01 Ohm Full-scale load current PGL = Low-Power Green DCA-20PC-6 0.001 Ohm 1 = 199.9A RL = Low-Power Red 2 = 1.999mA Power Supply: Shunt Input to Power Supply Isolation DC1 = +5-40Vdc, non-isolated power 3 = 19.99mA DCA-20PC-X-DC4 models only 500 Volts (available with -RL, -BL, or -PGL LEDs) 4 = 199.9mA Performance DC4 = +8-36Vdc, isolated power 5 = 1.999A (available with -RL, -BS, or -GS LEDs) Sampling Rate 2.5 reading per second 6 = 19.99A Accuracy 0.15%FS Accessories: DMS-20-CP Panel Cutout Punch Zero-Current Reading 001 000 001 Counts A DMS-BZL4-C bezel assembly with sealing gasket is Temperature Drift (0 = +60C) 0.2 0.4 Cnts/C supplied with each ammeter. Operating Supply Voltage (TB2 Terminals 1, 2 and 3) The noted full-scale values are the external load currents that the ammeter is DCA-20PC-X-DC1-XX +5.0 +40 Vdc designed to measure. This current enters TB-1 (-SHUNT), passes through the am- meters built-in shunt and exits via TB1-2 (+SHUNT). For all models, this same full- DCA-20PC-X-DC4-XX +8 +36 Vdc scale load current can also be routed, if the user so chooses, through TB2-1 and Operating Supply Current (TB2 Terminals 1, 2 and 3) TB2-2 (connection to positive rail of power supply). See detailed wiring diagrams. DCA-20PC-X-DC1-XX ( 5-40V) 10 15 mAdc Measuring positive and negative currents (bipolar operation): In applications where both positive and negative currents must be measured, Murata Power Solu- DCA-20PC-X-DC4-XX ( 8V) 100 150 mAdc tions recommends using -DC4 8-36V isolated supply models. Negative current DCA-20PC-X-DC4-XX ( 36V) 25 40 mAdc ow is denoted by the illumination of the displays negative (-) sign the absence of a negative sign implies positive current ow. Contact MPS if you have any ques- TB1 and TB2 Terminal Blocks tions regarding bipolar operation of DCA-20PC ammeters. Wire Size 12-20AWG, (solid) For all models, the application of 1.5 times the rated full-scale load current is 14-20AWG, (stranded) copper wire permissible as long as this overcurrent condition does not exceed 6 seconds and Insulation Strip Length 0.250 inches occurs no more than once in a 60 second interval (10% duty cycle). Screw Tightening Torque 4.4 pound/inches (0.5Nm) Breakdown (isolation) voltage applies only to -DC4 isolated-power models. Break- down voltage is tested with TB1-1 tied to TB1-2 (-SHUNT shorted to +SHUNT), Rated Current 20A with 12AWG solid copper wire and TB2-1, TB2-2, and TB2-3 all tied together (+V shorted to -V). 500Vdc is then 15A with 14AWG solid or stranded applied between the two shorted terminal-block pairs the maximum permissible copper wire leakage current is 5uA. Display Zero reading is measured with TB1-1 (-SHUNT) shorted to TB1-2 (+SHUNT). Display Type and Size 3 digit, 0.37 /9.4mm high red, blue or The Operating power supply voltage is applied to TB2-1-2 (+V) and TB2-3 (-V) green LED on -DC4 models, and to TB1-1 (-SHUNT) and TB2-2 (+V) on -DC1 models. On Overrange Indication1 for negative Vin all models, TB2-1 and TB2-2 are internally tied together (+V). Operating supply 1 for positive Vin current is the current which powers the meters analog and digital circuits it is measured with zero load-current passing through the ammeters built-in shunt Display Reading/Decimal Point Model dependent (i.e., with the display reading 000 and one decimal point enabled). Physical/Environmental On 5-40Vdc powered (-DC1), grounded-shunt models, the ammeters operating Operating Temperature 0 +60 C supply current enters TB1-1 (-Shunt) but is not included in the displayed reading (i.e., it does not pass through the built-in shunt). Storage Temperature 20 +75 C www.murata-ps.com/support MPM DCA-20PC.B07 Page 2 of 6