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Related Manuals for AEMC 725
Summary of Contents for AEMC 725
- Page 1 Clamp-On Harmonic Probe Model 725 USER MANUAL Model 725 AEMC HARMONIC METER I N S T R U M E N T S TDHF K FACTOR – + HOLD RECORD-PAUSE MAX MIN AVG RANGE SMOOTH THDF CFF RIPPLE AC + DC –...
- Page 2 Owner’s Record The serial number is located inside the battery compartment of your instrument. Please record this number and purchase date for your records. MODEL #725 CATALOG #2111.39 SERIAL #:_________________________________________________ PURCHASE DATE:_________________________________________ DISTRIBUTOR:___________________________________________...
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Page 3: Table Of Contents
Table Of Contents Warning ........... . 3 International Electrical Symbols . - Page 4 K Factor ........... 39 Transformer Harmonic Derating Factor (THDF) .
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Page 5: Warning
• ALWAYS inspect the instrument and accessory leads for serviceabil- ity prior to use, and replace defective parts immediately. • Never use the Model 725 on electrical conductors rated above 600 Vrms. International Electrical Symbols This symbol signifies that the Model 725 is protected throughout by double or reinforced insulation. -
Page 6: Receiving Your Shipment
Description The Clamp-On Harmonic Probe Model 725 is a portable, battery operat- ed power quality instrument. The Model 725 combines the simplicity and familiarity of digital clamp-ons with today’s critical information on power quality and harmonics. - Page 7 The DC functions incorporate the latest in Hall effect technology. Use the Model 725 as a comprehensive tool for troubleshooting as well as for daily measurements on circuits supplying traditional and today’s non- linear loads.
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Page 8: Specifications
Model 725 is built with GE Lexan ® and meets specific physical stan- dards — the instrument features a high level of safety. The Model 725 meets or exceeds UL 1244 safety standards as well as IEC 1010-1 Category III for 600 V ratings (UL ®... - Page 9 AC VOLTAGE (TRMS) Input Range: 0.05 to 600 Vrms ± 0.05 to ±1500 V Peak Basic Accuracy: 0.05 to 59.99 V: 1% R ±10 cts 60 to 1500 V peak: 1%R ±2 cts Input Impedance: 1 MΩ Frequency Range: 0.5 Hz to 5 kHz DC CURRENT Input Range: ±...
- Page 10 INDIVIDUAL HARMONICS Range: 0.2% to 300% (%THD or %DF) Rank: Hdc (DC component), H01 to H25 Resolution: 0.1% Accuracy: Distortion>10% and rank<H13: 5% R ±2 cts Distortion>10% and rank>H13: 10% R ±2 cts Distortion<10% and rank<H13: 10% R ±2 cts Distortion<10% and rank>H13: 15% R ±2 cts Frequency Range: Fundamental 40 Hz to 70 Hz, 25th order Display: Digital: %THD and Individual Harmonic value (A or V)
- Page 11 CREST FACTOR (CF) Range: 1.00 to 10.00 Resolution: 0.01 Minimum Input: >5 V or >5 A Accuracy (40 to 70 Hz): 1.00 to 3.50: 2% ± 2 cts 3.51 to 5.99: 5% ±2 cts 6.0 to 10.0: 10% ±2 cts Display: Digital: CF, Bar graph: True RMS (A or V) FREQUENCY (HZ) Range: 0.5 Hz to 20,000 Hz...
- Page 12 Material: Case: Gray Lexan ® 920A, UL 94 V2 Jaws: Red Lexan ® 500R, 10% fiberglass, UL 94 V0 LCD lens: Crystal Lexan ® 920A, UL 94 V1 Mechanical: Envelope Protection: IEC 529: IP 40 Drop Test: IEC 1010: 1m Vibration: IEC 68-2-6 Shocks: IEC 817 SAFETY...
- Page 13 50.7 mm (1.9") 92 mm (3.6") 27 mm (1.1") R 25 mm (.98") AEMC Model 725 HARMONIC METER I N S T R U M E N T S TDHF K FACTOR – + HOLD RECORD-PAUSE MAX MIN AVG RANGE SMOOTH THDF CFF RIPPLE AC + DC –...
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Page 14: Controls
Model 725 Controls 1. Jaw assembly: Transformer jaws opens to 1 1/8" (54 mm); accepts two 500 MCM 2. Rotary selection switch: OFF, V~ , A~, V - - - - - - 3. Lever/trigger: Opens or closes jaws 4. HOLD:... - Page 15 127 mm (5") 54 mm (2.13") AEMC Model 725 HARMONIC METER I N S T R U M E N T S TDHF K FACTOR – + HOLD RECORD-PAUSE MAX MIN AVG RANGE SMOOTH THDF CFF RIPPLE AC + DC –...
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Page 16: Digital Display Features
Digital Display Features The combination digital/analog display gives measurements on a large 4- digit LCD display. A fast responding analog bar graph display indicates trends or surges. To view full function display, continuously depress the HOLD push button while turning the rotary selector switch on. TDHF K FACTOR –... - Page 17 AVG. Average measurement value %THD % Total Harmonic Distortion THDF Transformer Harmonic Derating Factor (CBEMA) K Factor Transformer Derating Factor % Distortion Factor % Ripple Percent ripple on DC signal Crest Factor PEAK Peak (1 ms) measurement with ± sign H xx Individual harmonic order (Hdc to H25) Displays odd order harmonics only...
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Page 18: General Measurements Notes
General Measurement Notes • Validation of push button control is verified with a short beep (2 kHz). Invalid push button control is warned with a higher pitch beep (4kHz). Overload indication is a constant tone. • Maximum accuracy is achieved when the current carrying conductors are centered within the jaw assembly of the instrument. -
Page 19: Ac Voltage Measurements
AC Voltage Measurements AEMC Model 725 HARMONIC METER I N S T R U M E N T S OBSERVE ALL SAFETY PRECAUTIONS AND WARNINGS Operating Procedure 1. The voltage input connectors are color-coded 4 mm banana jacks located on the base of the instrument. When making voltage connec- tions, be sure to observe the proper polarity and connection integrity. - Page 20 Warning Though the meter can display to 1499 V in Auto Range and in the 600 V manual range, the warning triangle will be displayed above 600 Vrms. This indicates that the input exceeds the specified safety and operating range. The displayed value is only indicative and not speci- fied.
- Page 21 Displays the voltage frequency measurement. In HARM mode, Hz will also indicate the individual harmonic fre- quencies in the secondary portion of the display. RANGE Selects manual range on the digital display and bar graph: Digital Display: 0 – 100 0 –...
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Page 22: Ac Current Measurements
AC Current Measurements AEMC Model 725 HARMONIC METER I N S T R U M E N T S HOLD OBSERVE ALL SAFETY PRECAUTIONS AND WARNINGS Operating Procedure 1. Turn the rotary selection switch to the current measurement function A~. - Page 23 • bar graph display Select individual harmonics from Hdc, H01 to H25. The Model 725 will display the True RMS amplitude of the indi- vidual current harmonic as well as the percentage relative to the fundamental signal (%THD) or relative to the RMS value (%DF) whichever is selected prior to Displays frequency measurements.
- Page 24 K Factor Transformer K factor rating (HARM mode, yellow Shift push button). Crest Factor (yellow Shift push button twice). Peak Half cycle peak values (+ or -) Shift (yellow). In Peak mode: displays highest and lowest peak. Analog bar graph The analog bar graph will continue to display current Arms values while other measurement functions are displayed.
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Page 25: Dc Voltage Measurements
DC Voltage Measurements Model 725 Model 725 AEMC HARMONIC METER HARMONIC METER I N S T R U M E N T S – – + + TDHF K FACTOR HOLD RECORD-PAUSE MAX MIN AVG RANGE SMOOTH THDF CFF RIPPLE AC + DC –... - Page 26 Warning Though the meter can display to 1499 V in Auto Range and in the 600 V manual range, the warning triangle will be displayed above 600 V. This indicates that the input exceeds the specified safety and operating range. The displayed value is only indicative and not specified. Do not continue to operate the instrument when the input value exceeds the meter safety and operating specifications.
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Page 27: Dc Current Measurements
DC Current Measurements OBSERVE ALL SAFETY PRECAUTIONS AND WARNINGS Operating Procedure 1. Turn the rotary selection switch to the current measurement function . Selection is confirmed with a short beep when exiting OFF. - - - 2. Push and hold/DC zero.* Selection is confirmed with a short beep. After 3 seconds, a second beep will confirm (ZERO). - Page 28 The bar graph ranges are 60 A and 600 A. Overrange on the bar graph is indicated with The Model 725 incorporates the latest in DC Hall effect technology. Two Hall effect sensors mounted in a gap in the transformer core sense the magnetic field produced by the current being measured.
- Page 29 Peak Maximum DC value (+ or -), (yellow Shift push button). % Ripple Percentage AC ripple on DC signal (yellow Shift push but ton twice). Displays the highest and lowest peak values (Peak mode) Clamp-On Harmonic Probe Model...
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Page 30: Harm Push Button: Harmonic Measurements
HARM Push Button: Harmonic Measurements HOLD AC + DC For a current of 56.50 Arms (AC + DC) on second display and bar graph measurement of the total harmonic distortion (THD): 72.4% Harmonic measurements are initiated by pressing the HARM push but- ton. -
Page 31: Measuring Individual Harmonics
Measuring Individual Harmonics While in %THD or %DF, individual harmonic values may be accessed. Each harmonic is expressed in terms of it RMS magnitude and as a per- centage of the fundamental signal for %THD, and as a percentage of the RMS value for %DF. -
Page 32: Displaying Odd & Even Harmonics
Displaying Odd & Even Harmonics or Odd Harmonics Only The Model 725 may be set up to display odd & even harmonics or only odd harmonics. Pressing HARM while turning the Model 725 ON will select either odd + even or odd harmonic orders only. When only odd harmonics are set up, ODD is displayed on the LCD to the left of the har- monic order Hxx. -
Page 33: Distortion Factor (%Df)
(RMS) of the total signal. %DF Application Example: The Model 725 measures an RMS value of 100 A and a DF of 30%. This means that the harmonic content is 30% of the total RMS, or in other... -
Page 34: Cf: Crest Factor
CF: Crest Factor Crest Factor measurements are possible for A AC and V AC by depress- ing the yellow Shift push button twice. The crest factor is the ratio of the Peak value of the sinusoidal waveform to its RMS value. Peak value Crest Factor (CF) = RMS value... -
Page 35: Range Push Button: Manual Ranges
The RANGE push button enables you to exit the Auto Ranging mode and to enter manual ranges. RANGE operates on all measurement modes. RANGE will be displayed during manual ranging. In Amps AEMC Model 725 Model 725 AEMC HARMONIC METER HARMONIC METER... - Page 36 In Volts Pushing the RANGE push button will select a fixed manual range: 60 V first and 600 V on the second push. The digital display and the bar graph indicate the selected range. RANGE is displayed at the top of the display indicating a manual range selection.
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Page 37: Frequency Measurements
Hz Push Button: Frequency Measurement The Hz push button accesses the frequency function in either current or voltage. Frequency measurements are possible from 0.5 Hz to 20,000 Hz. The analog bar graph will continue to display current or voltage depend- ing upon which function is selected. -
Page 38: Peak/Smooth
Smooth Smooth stabilizes the digital readings when measurements fluctuate. In this mode, the Model 725 calculates and displays a three-second average reading. Smooth may be used in volts, amps, and frequency, as well as power quality functions (%THD, %DF, CF). -
Page 39: Min/Max Recording
HOLD. Recording is initiated with the MIN/MAX push button during the AEMC Model 725 HARMONIC METER I N S T R U M E N T S selected measurement function. – – + +... -
Page 40: Recording With Time Indication
Recording With Time Indication The clock function may be toggled ON/OFF with ON and Hz. The time format indicator is displayed in the upper right corner in the fol- lowing format: 00:00 (HH:MM). The clock is stopped by using the HOLD key. -
Page 41: K Factor
K Factor K-Factor information can be accessed while measuring AC current with the rotary switch set to A~ in the HARM mode by pushing the yellow (Shift) key. The K factor can be thought of as an index of the transformer’s ability to handle nonlinear load current without abnormal heating. -
Page 42: Transformer Harmonic Derating Factor (Thdf)
THDF (Transformer Harmonic Derating Factor) THDF is accessed through A~. Push the (yellow) Shift button three times to sequence to THDF. THDF is a method of calculating transformer derating established by the Computer and Business Equipment Manufacturers Association (CBEMA) for phase-to-neutral loads. This derating factor can be applied to electrical systems with high third harmonic current and high crest fac- tor, and can be helpful where large portions of the load consist of single- phase switch mode power supplies. -
Page 43: Battery Test & Replacement
Battery Test & Replacement To determine useful battery life, a self-test may be initiated by pressing the Shift (yellow) push button and holding for longer than 3 seconds. Current battery voltage is displayed along with an indication, in hours, of approximate battery life remaining. -
Page 44: Auto-Off Feature
Auto-Off To conserve battery life, the Model 725 automatically shuts itself off after 10 minutes under the following conditions: • No push button action • No rotary switch (A, V) action • Not in Record mode Six short beeps will be heard prior to shutdown. Any control action will repower the instrument. -
Page 45: Repair, Maintenance & Calibration
Maintenance To clean the Model 725, wipe the case and jaw covers with a damp cloth and mild detergent. Do not use any abrasives or solvents. Repair and Calibration... -
Page 46: Technical Assistance
Technical Assistance If you are experiencing any technical problems, or require any assistance with the proper use or application of this instrument, please call our technical hotline: (800)343-1391 • Fax (508)698-2118 Clamp-On Harmonic Probe Model... - Page 47 Clamp-On Harmonic Probe Model 725 ® AEMC I N S T R U M E N T S AEMC Instruments• 200 Foxborough Blvd.• Foxborough, MA 02035-2872...