ACM3P Series www.murata-ps.com Three-Phase AC Ammeters Actual size C US E156931 ® FEATURES PRODUCT OVERVIEW „„ Measure and display the true-rms current of 3-phase Murata Power Solutions’ ACM3P series 3-phase AC ammeters measure and display the power systems true-rms values of 2- or 3-phase ac mains current. A front panel touch switch enables the „„ selection of a continuous reading of any of the three phases. All ACM3P ammeters are func- Universal 85-264Vac (47-63Hz) operating supply range tionally complete, with built-in L1, L2, and L3 current transformers—no other user-supplied components or hardware are required. „„ Three built-in current transformers measure up to 100A per phase ACM3P series AC ammeters are available with a 0-100A input range (150A peaks) and „„ Ideal for power distribution units (PDUs) and backup provide a resolution of 0.1 Amp. Their 85-264Vac (47-63Hz) operating supply range makes power systems these ammeters perfect for worldwide 3-phase current monitoring applications. And, unlike conventional average-responding products, ACM3P ammeters can accurately display the „„ Low power consumption: less than ¼watt from 120Vac supply true-rms values of triangle waves, square waves, and other irregularly shaped AC current waveforms, with an accuracy of ±2% of full scale. „„ One-piece polycarbonate housing fits ‘0U’ & ‘1U’ rack spaces Their large (0.36"/9.2mm), bright LED display, available in a choice of red, blue, or green, „„ Low-profile surface mount design occupies minimal enables ACM3P ammeters to be easily readable from as far as 15 feet (5 meters). All behind-the-panel space units are packaged in a one-piece, vibration resistant, polycarbonate housing that can be installed in vertical ‘0U’ or horizontal ‘1U’ rack spaces. Their miniature size is ideal for UPS „„ Available in red, green, or blue LED-displays with backup power sources, power strips, alternative energy metering, and any other applica- phase annunciators tions that require precise monitoring of 2- or 3-phase ac current. „„ Low Cost; approvals to UL/cUL/IEC/61010-1 SIMPLIFIED SCHEMATIC DIAGRAM L1 L2 L3 PHASE 1 +5V L1 PHASE 2 L2 A/D PHASE 3 CONVERTER L3 +5V CURRENT B +5V LIMITED 85-264 Vac AC/DC MICRO- A 47-63 Hz CONVERTER CONTROLLER SUPPLY For full details go to www.murata-ps.com/rohs SEL www.murata-ps.com/support MPM_ACM3P Series.C01 Page 1 of 6 ACM3P Series Three-Phase AC Ammeters Performance/Functional Specifications Typical at TA=+ 25ºC, 120Vac @ 50Hz, unless otherwise noted Measurement Limits Min. Typ. Max. Units TECHNICAL NOTES AC (rms) Current, L1, L2, L3 ➀ 0.0 — 100.0 Amperes IMPORTANT! To ensure safe and reliable operation, ACM3P amme- 1.5 x Rated full-scale current Overcurrent Rating ➁ ters must be installed and serviced by qualified technical personnel. Performance ! Contact Murata Power Solutions if there is any doubt regarding their installation or operation. Sampling Rate 1.5 samples/sec 1. Measurement Type: ACM3P series 3-phase ammeters employ a Current Accuracy ➂ ±2% ±3% precision energy metering integrated circuit and a low-power micro- Measurement Bandwidth (L1, L2, L3) 14kHz controller to measure and display the rms value of 2- or 3-phase Temperature Drift (0 to 60ºC) 0.5 Counts/ºC ac-mains current. However, while the unit has an upper bandwidth Zero-Current Reading (within 1 sec.) 1 Counts of 14kHz, dc components or frequencies below 47Hz will not be UL/IEC61010-1 Measurement category II measured accurately. Supply Voltage (TB1) 2. Basic Operation: Upon application of ac power to TB1, the unit will All Models 85 120 264 Vac/47-63Hz first perform a self-test routine and then continuously display am- peres, with one of the three phase-annunciator LEDs illuminated (L1, Supply Current ➃ L2, or L3). The display will remain fixed in one of these reading modes ACM3P-X-AC1-R-X-C 35 50 110 mA as long as the front panel ‘SEL’ button is not touched. Assuming phase ACM3P-X-AC1-G-X-C 50 75 165 mA L1 is initially illuminated, momentarily touching the ‘SEL’ button two ACM3P-X-AC1-B-X-C 50 75 165 mA times in succession will cycle the display to phase L2, and then to Power Supply Terminal Block (TB1) phase L3. Momentarily touching ‘SEL’ a third time will return the unit Wire Size 16-22AWG, solid or stranded back to displaying phase L1 current. Insulation Strip Length 6.4mm (0.250 in) If power is removed and then restored, the ACM3P will perform a Screw Tightening Torque 0.4Nm (3.6 lb-in) self-test and then return to displaying the last selected phase, i.e., the phase it displayed just before power was removed. Rated Voltage 300Vac Configuring for 2-Phase Operation: As shipped, ACM3P ammeters Display are configured to measure and display 3-phase currents (L1, L2, and Display Type and Size 4 Digit LED, 9.14mm (0.36in) high L3 current transformers are all active). The unit can be set to display Overrange Indication Flashing display 2-phase currents (only L1 and L2 are active) by performing the follow- Decimal Point Selection Automatically Set ing procedure: Physical/Environmental A. Press and hold the SEL button for approximately five seconds and Operating Temperature: 0 — +60 ºC then release the button once the words “LinE SEt” appear on the Storage Temperature: -40 — +75 ºC display. Humidity (non-condensing): 0 — 85 % B. Briefly tapping the SEL button will alternate the display reading Dimensions: See mechanical specifications between ‘2-Ph’ and ‘3-Ph’ each time SEL is tapped. Weight, all models 2.6 oz (74g) C. To change the factory default 3-phase mode to 2-phase, leave the display fixed in the ‘2-Ph’ reading for at least five seconds. Notes ➀ Specified full-scale currents are those passing through the power meter’s built-in current To revert the unit back to 3-phase operation simply repeat the above transformer’s primary load-circuit. See Notes 2 and 3 below for additional information. procedure but, in step C, allow the unit to display a fixed ‘3-Ph’ for at ➁ The overcurrent rating of 1.5 x the rated full-scale current is a continuous rating and applies to the current passing through the built in current transformer. Accuracy is guaranteed up to the least five seconds. rated current level. ➂ Power Meters are calibrated with near full-scale 50Hz sine-wave inputs. ACM3P ammeters with manufacturing date codes of June 2016 or ➃ All specified maximum supply currents are steady state. Larger surge currents can occur at later have the additional ability to continuously scroll (“auto-scroll”) initial application of line power. through all 3 phases, or auto-scroll through only 2 phases. The process for configuring the ACM3P for auto-scrolling operation begins by first holding down the ‘SEL’ switch for five seconds to enter ORDERING INFORMATION the programming mode that is indicated by the display showing “LinE SEt.” ACM3P-4-AC1-R-C 100A, 85-264Vac Supply, Red LED Display After the unit displays “LinE SEt,” immediately and repeatedly ACM3P-4-AC1-G-C 100A, 85-264Vac Supply, Green LED Display pressing and releasing the SEL switch will cycle the unit through the ACM3P-4-AC1-B-C 100A, 85-264Vac Supply, Blue LED Display following four operating-mode options: ACM3P-4-AC1-B-28-C 100A, 85-264Vac Supply, Blue LED Display, 28 inch lead length continued on next page www.murata-ps.com/support MPM_ACM3P Series.C01 Page 2 of 6 ACM3P Series Three-Phase AC Ammeters 2P-A > 3P-A > 2P > 3P used to supply power to external loads. The supply wires feeding these power meters must be fused with a 0.5A/250V time delay/time lag fuse, Where: in accordance with applicable regulatory codes. 2P-A enables continuous auto-scrolling 2-phase operation Wire insulation must be stripped to within ±10% of the stated dimen- 3P-A enables continuous auto-scrolling 3-phase operation sions, and wires should be inserted into TB1 such that their insulation is 2P enables fixed 2-phase operation not pinched by the screw terminal. 3P enables fixed 3-phase operation 7. Current Transformer Phasing: Since the ACM3P only measures am- To enable the desired mode of operation, simply stop pressing the SEL peres, transformer phasing is not required. ‘Phasing’ refers to the direc- switch after the desired mode is displayed. The unit will begin normal tion of the current-carrying wire as it passes through the primary hole of operation in the selected mode five seconds after the last SEL switch each of the three built-in current transformers. activation. 8. Connector Torque Ratings: It is important to tighten TB1’s screw- 3. Overrange Indication: ACM3P ammeters have an overcurrent rating of terminals to their rated torque specification of 3.6 pound-inches (0.4Nm). 1.5 times rated current, or 150A. However, accuracy is only guaranteed Proper tightening will minimize connector losses and ensure safe, reliable up to 100A, and the display will flash on and off when the current is at or operation. above 120A. 9. Isolation: Except for the 2-56 thread metallic mounting studs, all of the 4. Calibration: Due their digital design, ACM3P ammeters cannot be cali- ACM3P ammeter’s internal components (printed circuit board, resistor, brated in the field. ACM3P ammeters are factory-calibrated to meet their capacitors, current transformers L1, L2 and L3’s secondary leads, etc.) specified accuracies with the factory supplied current transformers. Use are at the ac-mains potential connected to TB1. ACM3P ammeters are of any other current transformers will produce significant errors. designed to be powered from one ac power-source only. Any other con- Contact Murata Power Solutions if additional information is required nection schemes could introduce significant measurement errors. regarding calibration, setup, or any other technical issue pertaining to The three built-in current transformers have a dielectric breakdown ACM3P ammeters. rating of 2kV minimum, allowing them to safely monitor 480V, 3-phase 5. Wiring: All power supply and load wiring must be rated for the voltages ac mains currents. This dielectric rating pertains only to the insulated and currents they will carry and must comply with any code or applica- load-carrying wire as it passes through the built-in CT’s primary hole. tion-mandated requirements pertaining to the user’s specific installation. However, attention must still be paid to ensure adequate wire-to-wire 6. Supply Fusing, and Grounding: Wires specified in the Functional spacings, and wire-to-metallic surface spacings. Properly rated wiring Specifications section must be used for making connections to ACM3P and fusing must be used for all installations, as noted in Technical Notes series ammeters’ TB1 terminal block. No connection is required for earth/ 5 and 6 above. chassis ground. IMPORTANT: Even though ACM3P ac ammeters can be used in 480V cur- ACM3P series ammeters are not internally fused. Terminal block TB1 is to rent monitoring applications, the ac supply connected to TB1 must never be used only for powering the ammeter's internal circuitry; it must not be exceed the maximum rating of 264V/47-63Hz. PANEL INSTALLATION PANEL All connections to ACM3P ammeters must be made after the unit is securely attached to the panel, and with all associated load and supply 2-56 Hex Nuts (4 places) voltages de-energized (off), using extreme caution and observing all Tighten each nut to 15 to 20 safety measures applicable to the user’s installation. ozf-in (0.106 to 0.140 N-m). ACM3P Care should be exercised when passing conductors through the am- meter’s built-in current transformers L1, L2, and L3. The installed wire- positions should be such that minimal mechanical forces are applied L1 to the current transformers, TB1, or to the ACM3P ammeter itself. In high- vibration environments, it is strongly recommended that strain reliefs be L2 used for all wiring. Using Figure 1 as a guide, carefully insert the ACM3P assembly into the L3 panel opening. From the rear of the panel, install and then tighten the four #2-56 hex nuts over the threaded studs. Tighten each nut to 15 to 20 ozf-in (0.106 to 0.140 N-m). Use only the factory-supplied hardware as the use of substitute hardware could result in an unsafe installation and/or adversely affect the reliability of the installation. The recommended panel thickness range that can be used with the sup- plied hardware is 0.040 inches (1.0mm) to 0.25 inches (6.4mm). Panel thicknesses outside of this range may require additional user-supplied SIDE VIEW hardware or modifications. Figure 1. Panel Installation www.murata-ps.com/support MPM_ACM3P Series.C01 Page 3 of 6 Panel Cutout ACM3P Series Three-Phase AC Ammeters TYPICAL WIRING DIAGRAMS PHASE A PHASE B L1 L2 L1 L2 TB1 B A L3 Note: Line and phase currents are the same for Wye systems. Fuse* L3 85–264 Vac 47–63 Hz PHASE C Figure 2. Wiring diagram Wye systems *See technical note 6. L1 L1 PHASE A L2 PHASE B B TB1 L2 A L3 Fuse* L3 PHASE C 85–264 Vac 47–63 Hz Figure 3. Wiring diagram for Delta systems monitoring line current *See technical note 6. PHASE B L1 L2 L2 TB1 B A L1 L3 PHASE A PHASE C Fuse* L3 85–264 Vac 47–63 Hz Figure 4. Wiring diagram for Delta systems monitoring phase current *See technical note 6. www.murata-ps.com/support MPM_ACM3P Series.C01 Page 4 of 6 L1 L2 L3 ACM3P Series Three-Phase AC Ammeters PANEL CUTOUT RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS INTERNAL CORNER RADII: 0.032 (0.81) MAX. The panel opening must be centered vertically and 1.07 0.870 horizontally between the four 0.093 (2.362mm) (27.18) (22.10) diameter holes. 1.426 (36.22) 1.626 (41.30) 0.093 (2.362) DIAMETER (4 REQUIRED) MECHANICAL SPECIFICATIONS 0.51 2.10 (53.3) Dimensions are in inches (mm). (12.95) 0.12 (3.05) (min) Tolerances (unless otherwise specified): .XX ± 0.02 (0.51) .XXX ± 0.010 (0.254) 1.43 1.07 Angles ± 2˚ Side View (36.3) (27.20) L1 L2 L3 Components are shown for reference only. SEL MULTI-PHASE AC AMMETER 0.12 (3.05) (min) 0.40 (10.16) Front View 0.086 DIA (REF) 0.60 B TB1 2-56 UNC THREAD (15.24) (max) A 0.22 (5.59) 0.33 (8.39) (min) (min) 1.63 (41.4) Back View Bottom View Diameter: Inner: 0.57 (14.5) Outer: 1.175 (29.8) CT Lead Length: Standard: 5.0” (127mm) min. Optional: 28.0” (700mm) min. on blue LED model www.murata-ps.com/support MPM_ACM3P Series.C01 Page 5 of 6 ACM3P Series Three-Phase AC Ammeters 1. Description of safety marks: Caution, risk of electrical shock Caution, risk of danger Equipment is protected throughout by double or reinforced insulation 2. Cleaning Instructions: Gently clean with dry cloth only. 3. Caution: if the equipment is used in a manner not specified by Murata Power Solutions, the protection provided by the equipment may be impaired. NOTES This product is subject to the following operating requirements Murata Power Solutions, Inc. and the Life and Safety Critical Application Sales Policy: 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. Refer to: http://www.murata-ps.com/requirements/ ISO 9001 and 14001 REGISTERED 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. © 2017 Murata Power Solutions, Inc. www.murata-ps.com/support MPM_ACM3P Series.C01 Page 6 of 6