ACA5-20PC Series 5 Amp Input LED-Display AC Ammeters C FEATURES ■ Scales and displays the output of 50:5A to 2000:5A current transformers ■ 14 ranges (0-50 Amp to 0-2000 Amp) ■ 2 Power options, 28 models ■ Functionally complete: On-board 5A current transformers Scaling/interface circuitry Precision A/D converters Bright red or green LED displays ® US E156931 ACA5-20PC Series AC Ammeters are designed to scale and digitally display the output of standard, 5A-output current transformers (50:5A, 500:5A, 1000:5A, etc.). Simply pass the secondary/output wires of the "primary" CT through the ACA5-20PC's on-board CT, apply power to the meter, and you're instantly measuring ac currents over one of 14 ranges from 0-50A (with 100mA resolution) to 0-2000A (with 1A resolution). Because they accept outputs from previously installed high-current CT's, ACA5-20PC's can instantly bring modern digital precision to older ac ammeters. The functionally complete ACA5-20PC ammeters incorporate scaling/interface circuitry to mate the on-board CT to a precision (3½ digit) A/D converter. The A/D's output directly drives the meters' large (0.37"/9.4mm digit height), easy-to-read, LED displays. All models employ auto-zero circuits, precision bandgap references, and super stable metal-film resistors for unsurpassed accuracy (±0.15%FS) and stability. ■ Subminiature, 1.38" x 0.88" package ■ Easy-to-read, 0.37"/9.4mm digits ■ AC powered models: 120/220Vac @ 50/60Hz ■ AC models can be "self-powered" ■ +5-40V dc powered model ■ 2000V isolation; UL/CSA recognized ■ Digital replacements for analog ammeters ACA5-20PC meters are either ac (120/220Vac @ 50/60Hz) or dc (+5-40V) powered. AC models can be powered by the same ac supply whose current they are monitoring. All ACA5-20PCs provide 2000Vdc isolation between the measured ac current and their power supply, and all models are UL/CSA recognized. Each meter is housed in a subminiature, 1.38" x 0.88", epoxy-encapsulated package whose behind-the-panel installation depth is 2 inches. Display color options include standard red, high-intensity red, and standard green. Each meter is supplied with a plastic bezel assembly with sealing gaskets (MPS DMS-BZL4-C). SIMPLIFIED SCHEMATIC DRAWING � � � � � � � � �� �� �� � � � �� �� � � � � � �� � � � � � � � � �� �� � � � � � �� � �� � � � � � � �� � � � � � �� �� � � � � � �� �� � � � � � � � � � � � � � � � � � ��� � � � � � � � � � � � � � � � � � � � � � � � � For full details go to www.murata-ps.com/rohs � � �� � � � � � � � � � � � � � � �� � � � � � � � � � � � � �� ��� � �� � � � �� � � � � www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MPM_ACA520PC_B02 Page 1 of 5 ACA5-20PC Series 5 Amp Input LED-Display AC Ammeters Performance/Functional Specifications Typical at TA = + 25°C, unless otherwise noted. Full-Scale Current ➀ ➁ All Models Ordering Information Min. Typ. Max. Units – – 5.0 Amps ACA5 - 20PC - 1 - AC1 - RL - C Input Range: (45-450Hz) 1.5 x rated full-scale current Overcurrent Rating ➀ Performance Sampling Rate 2.5 reading per second Accuracy ➁ ±0.15%FS ±6 Counts Measurement Type Temperature Drift (0 = +60°C) Zero Reading Dielectric Withstanding Voltage 1 = 50.0A 2 = 75.0A 3 = 100.0A 4 = 150.0A 5 = 199.9A 6 = 250A 7 = 300A 8 = 400A 9 = 500A 10 = 600A 11 = 750A 12 = 1000A 13 = 1500A 14 = 1999A Sine wave input, full-wave averaging, rms calibrated – ±0.2 ±0.4 Cnts/°C “–001” “000” “001” Counts 2000 – – Vdc Power Supply Voltage ➂ ACA-20PC-X-AC1-RL (47-99Hz) ACA-20PC-X-DC1-RL 85 120 264 Vac +4.75 – +40 Vdc Power Supply Current ➃ ACA-20PC-X-AC1-RL (47-99Hz) – 30 50 mA ACA-20PC-X-DC1-RL – +8 +12 mAdc 3.6 pounds/inches (0.4Nm) TECHNICAL NOTES Display Display Type and Size 3½ digit, 0.37"/9.4mm high LED Overrange Indication “1_ _ _“ Decimal Point Model dependent. See Ordering Info. Physical/Environmental Operating Temperature Storage Temperature Humidity (non-condensing) Case Material Dimensions Weight: (All models) For fu www.mur Matching 5A Current Transformers: 5A current transformers for all ACA5-20PC ac ammeters are available from Murata Power Solutions at nominal cost. For technical information, visit www.murata-ps.com, select Digital Panel Meters, then Accessories. 0.25 inches Screw Tightening Torque Power Supply: AC1 = 85-264Vac@50/60Hz DC1 = +5-40Vdc A DMS-BZL4 bezel assembly with sealing gasket is supplied with each ammeter. 16-22AWG (solid or stranded) Insulation Strip Length LED Color: RL = Red Standard Accessories: DMS-20-CP Panel cutout punch Power Supply Terminal Block Wire Size and Type Add -C for RoHS 5A CT Partno. 7020-01036-0 7020-01037-0 7020-01038-0 7020-01039-0 7020-01040-0 7020-01041-0 39-3681407 * 39-3681408 * 39-3681409 * 7020-01042-0 7020-01043-0 7020-01044-0 7020-01045-0 7020-01046-0 * Not RoHS Compliant 0 – +60 °C –40 – +75 °C 0 – 95 % Polycarbonate 1.38”W x 0.88”H. Depth is model dependent (see mechanical specification) 1.1 Ounces (31 grams) ➀ The specified Full-Scale Current is the current carried by the single wire passing through the center hole of the ACA5-20PC's on-board CT. It is not the load current ultimately being measured. the Overcurrent Rating is a continuous rating that applies to the Full-Scale Current. It does not apply to any circuitry external to the meter. ➁ Listed accuracy specifications apply over the range of the Rated Full-Scale Current over frequencies of 45-450Hz. ➂ Maximum reverse polarity protection on "DC1" models is –40Vdc. ➃ All specified maximum power supply currents are steady-state. AC-powered models can draw larger surges at initial turn on. IMPORTANT! To ensure safe and reliable operation, ACA5-20PC ammeters must be installed and serviced by qualified technical personnel. Contact Murata Power Solutions if there is any doubt regarding ammeter installation and/or operation. 1. Measurement Type: ACA5-20PC ac ammeters employ a full-waverectified, average responding, rms-calibrated circuit to measure the stepped-down output of their built-in L1 current transformer (CT) . Stated accuracy specifications are measured using a sine-wave current at or close to the full-scale input level, at nominal line frequency. 2. Calibration: Periodic recalibration of ACA5-20PC 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 ACA5-20PC 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 access the recessed calibration potentiometer located on the back of the meter (see Mechanical Specifications). Contact MPS if additional information is required regarding calibration, setup, or any other technical issue pertaining to ACA5-20PC ammeters. 3. Wire Gauges and Fusing: Wires specified in the Functional Specifications section must be used for making connections to ACA5-20PC Series ammeters. All power-supply and load wiring must be rated for the supply voltages and currents they will conduct and must comply with any code or application-mandated requirements pertaining to the user’s specific installation. www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MPM_ACA520PC_B02 Page 2 of 5 ACA5-20PC Series 5 Amp Input LED-Display AC Ammeters The supply wires connected to both the meter and the load must be fused according to the current rating of the wire gauge being used, in accordance with applicable regulatory codes. Also, wire insulation should be stripped to within +/–10% of the stated dimensions, and wires should be inserted into TB1 such that their insulation is not pinched by the screw terminal. TB1 is to be used only for powering the meter’s internal circuitry. It must not be used to supply current to external loads. Therefore, implementing connections to any 5A current transformer’s output leads must only be performed with zero load-current, that is, with no power applied to the load circuit. 9. CT Connections and Grounding: Some applications require connecting one of the external 5A CT’s output leads to earth/chassis ground. In the USA, consult the latest revision of the National Electrical Code (NEC) for more information regarding CT grounding. AC-powered models draw minimal steady-state supply currents (50mA max.), and in most applications, they can be fused according to the supply wire’s maximum amperage rating. However, these models can draw significantly higher surge currents for brief periods when the ac line voltage is initially applied. After all mechanical assembly is completed, connect the two output leads of the external 5A CT to each other after they are run through L1’s center hole. Pressure-style connectors (commonly refered to as “wire nuts”) are acceptable as long as they are rated for the number of conductors and voltage invloved. 10. Replacing Analog Panel Meters: ACA5-20PC ammeters can be used as direct replacements for analog panel meters driven by 5A CT’s. All wiring operations must be performed with both the load and the supply power sources completely de-energized. 4. AC Supply Polarity and Grounding: The two supply inputs, TB1-A and TB1-B, on all ac-powered ACA5-20PC ammeters are not in themselves polarity sensitive, that is, they have no internal "AC LO" or "AC HI" designations. Also, ac-powered ACA5-20PC ammeters do not include or require a connection to earth/chassis ground. PANEL INSTALLATION 5. Connector Torque Ratings: It is important to tighten TB1's, screwterminals to their rated torque specification of 3.6 pound-inches (0.4Nm). Proper tightening will minimize connector losses and ensure safe, reliable operation. All connections to ACA5-20PC Series ammeters must be made after the ammeter is securely attached to the panel and with all load and supply voltages de-energized (off). 6. DC-Powered Models: DC-powered models draw minimal supply currents (120mA max.) and in most applications can be fused according to the supply wire’s maximum amperage rating. However, be sure to check and comply with all applicable codes and regulations to ensure proper installation and operation. Care should be exercised when passing conductors through the ammeter’s built-in CT. The installed wire positions should be such that minimal forces are applied to the built-in CT, TB1, or to the ammeter itself. In high-vibration environments, proper strain reliefs must be used for all load and supply wiring. 7. Isolation: The on-board CT (L1) provides a minimum 2000Vdc isolation between the current-carrying conductor passing through its primary circuit and the ammeter supply voltage connected to TB1. This isolation rating only applies to applications in which the load wiring (i.e., the wire passing through L1’s center hole) does not connect directly or indirectly to TB1-A or TB1-B. To ensure a secure panel-mount installation, MPS recommends using the DMS-BZL4-C bezel assembly (with sealing gasket) supplied with each ammeter. See Mechanical Specifications for detailed cutout and ammeter dimensions. 8. CT Precautions: In normal operation, a 5A current transformer’s secondary circuit operates at a very low voltage due to its closedloop operation and its low burden resistance. However, a CT can still generate potentially lethal voltages if its output current is suddenly interrupted. For example, loose CT secondary connections can cause a condition referred to as “inductive kick". Inductive kick can generate extremely high voltages across intermitent secondary connections. Following the four-step sequence shown in Figure 2 — being careful not to apply excessive force or twisting motions — insert the ammeter into the panel opening. When using the DMS-BZL4-C, install its sealing gasket so it is positioned between the ammeter’s front flange and panel front surface (see Mechanical Specifications). Be sure to use and securely tighten all four screws supplied with the bezel assembly. Step 1. Step 2. Step 3. � � � � � � � � � � Step 4. � � � � � � � � � � � � � � � � � � � Figure 2. Panel Installation www.murata-ps.com � � � � � � � � � ��� � � �� Technical enquiries email: [email protected], tel: +1 508 339 3000 MPM_ACA520PC_B02 Page 3 of 5 ACA5-20PC Series 5 Amp Input LED-Display AC Ammeters TYPICAL WIRING DIAGRAMS First pass and carefully dress one output wire from the external CT through the on-board CT (L1). Then connect the ac supply to TB1 as shown. If required, verify that correct line-power polarities are applied to the external load (see Technical Note 4). Ensure all wires are stripped and terminals torqued correctly. For proper operation, pass only a single wire through the on-board CT's center hole. � � � � �� � � � �� �� � � � � �� � � � � � � � � � � � � � � � � � � � � � � �� � � � � �� � � � � � � � � � � � � � � � � � �� � � � � � �� � � � � � � � � � � � � � � � � � Figure 3. ACA5-20PC AC-Powered Models First pass and carefully dress one output wire from the external CT through the on-board CT (L1). Then connect the two dc powersupply wires to TB1, observing correct positive ("+") and negative ("–") polarities. Ensure all wires are stripped and terminals torqued correctly. For proper operation, pass only a single wire through the on-board CT's center hole. � � � �� � � � � � � � � � � � � � � � �� � � � �� �� � � � � � � � � � � � � �� � � � � � � � � � � � � � �� � � � � � �� � � � � � � � � � � � � � � � � � � � � � � �� � � � � � � � Figure 4. ACA5-20PC DC-Powered Models www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MPM_ACA520PC_B02 Page 4 of 5 ACA5-20PC Series 5 Amp Input LED-Display AC Ammeters MECHANICAL SPECIFICATIONS � � � � � ��� � � � � � � � �� � � � �� �� �� � � �� � �� � �� � �� � �� � �� �� � Tolerances inches (mm): 2 PL DEC ±0.02 (±0.51), 3 PL DEC ±0.010 (±0.254) � �� � �� � �� � � �� � � �� �� � � � � � �� � � �� �� � � � �� � �� � �� � � �� � �� � �� � � �� � �� � �� � � �� � �� � �� � � � � � � � �� � �� � �� � � � � � � � �� �� � � � �� � � �� �� � � � �� � �� � �� � � � � � �� �� � � � � � � � � � � � � � � � � � � � ��� � � �� � � � � � BEZEL INSTALLATION AND RECOMMENDED DRILL AND PANEL CUTOUT � � � �� � � � �� � � � � � � � � � �� �� � � � �� � ��� � � � � � �� � � ��� �� � ��� � � � DMS-BZL4-C BEZEL � � � � � � � � � � � �� � �� � �� � � �� � � � � �� � � � � � �� �� � � � �� � � � �� � � ��� �� � � ��� �� � � � � � ��� �� � � � �� � � � � � � � �� � � � �� � �� � �� � � �� � � � �� � � � � �� � � � � � � � � �� � � �� �� � � �� � � � � � � �� � � � � � �� � � ��� � �� � � ��� �� � ��� � � � � �� � � �� � �� � � � �� � �� � �� � � � �� � � �� � �� � � � �� � � ��� � �� � � � �� � � ��� � �� � � � �� � � �� �� � � � �� � � ��� �� � � � �� � � ��� � �� � � Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 www.murata-ps.com email: [email protected] ISO 9001 and 14001 REGISTERED 11/24/08 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. Specifications are subject to change without notice. © 2008 Murata Power Solutions, Inc. www.murata-ps.com USA: Mansfield (MA), Tel: (508) 339-3000, email: [email protected] Canada: Toronto, Tel: (866) 740-1232, email: [email protected] UK: Milton Keynes, Tel: +44 (0)1908 615232, email: [email protected] France: Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: [email protected] Germany: München, Tel: +49 (0)89-544334-0, email: [email protected] Japan: Tokyo, Tel: 3-3779-1031, email: [email protected] Osaka, Tel: 6-6354-2025, email: [email protected] China: Shanghai, Tel: +86 215 027 3678, email: [email protected] Guangzhou, Tel: +86 208 221 8066, email: [email protected] Singapore: Parkway Centre, Tel: +65 6348 9096, email: [email protected] Technical enquiries email: [email protected], tel: +1 508 339 3000 MPM_ACA520PC_B02 Page 5 of 5