Low Frequency Measuring System - EMC

Emission Measurements
Brief Overview of Phenomena . . . . . . . . . . . . . . .
Applicable Standards . . . . . . . . . . . . . . . . . . . 3
Test System Overview . . . . . . . . . . . . . . . . . .
Generator Specifications . . . . . . . . . . . . . . . . .
Accessories and Options . . . . . . . . . . . . . . . . . 10
EMC PARTNER’s Product Range . . . . . . . . . . . . . . 11
Emission Measurements: LF Measuring System
Brief Overview of Phenomena
Low Frequency (LF) Measuring System measures and simulates disturbances in the
230V/50Hz and 115V/60Hz public power supplies.
The following phenomena can be tested:
The increasing use of electronic equipment fitted with switch mode power supplies
has led to an increase in distortion of the public power supply. Such loads draw
non sinusoidal current, which contains harmonic frequencies at multiples of the
50Hz and 60Hz supply frequencies. This can lead to significant currents flowing in
the neutral conductor resulting in cable and transformer overheating. This is also
known as „phantom power“ because it has to be transported through cables and
transformers, but is not useful.
Small variations in the mains supply voltage, caused by fluctuating currents interacting
with the mains impedance, influence the light intensity of an incandescent bulb. Light
intensity fluctuates as a square of the RMS voltage. These cyclic fluctuations called
„flicker“ are not noticed by the human eye but are registered by the brain, causing
annoyance and increased stress. In extreme cases they can trigger headaches or
epileptic attacks in susceptible people. Power factor correction is a simple means
of reducing flicker.
Non linear loads connected to the public power supply generate harmonic and
interharmonic currents which are transmitted throughout the power network to
other equipment. Mains networks are also used to transmit control and monitoring
signals. It is necessary to ensure that these unwanted frequency components do
not cause disruption to control or measurement units.
- Voltage variation
Changes in load conditions on the public power main, can cause voltage deviations
both in a positive (overvoltage) and negative (undervoltage) direction. Equipment
must be capable of maintaining normal operation during such deviations.
Emission Measurements: LF Measuring System
Applicable Standards
International Electrotechnical Committee (IEC)
IEC 61000-3-2 (Ed.3.2: 2009): Limits - Limits for harmonic current emissions (equipment input current <= 16 A per phase)
IEC 61000-3-3 (Ed.2.0: 2008): Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current
<= 16 A per phase and not subject to conditional connection
IEC 61000-4-7 (Ed.2.1: 2009): Testing and measurement techniques - General guide
on harmonics and interharmonics measurements and instrumentation, for power supply
systems and equipment connected thereto
IEC 61000-4-15 (Ed.1.1: 2003): Testing and measurement techniques - Flickermeter
- Functional and design specifications
IEC/TR 60725 (Ed.2.0: 2005): Consideration of reference impedances and public supply network impedances for use in determining disturbance characteristics of electrical
equipment having a rated current = < 75 A per phase
IEC 61000-4-13 (Ed.1.1: 2009): Testing and measurement techniques - Harmonics
and interharmonics including mains signalling at a.c. power port, low frequency immunity tests.
IEC 61000-4-14 (Ed.1.2: 2009): Testing and measurement techniques - Voltage fluctuation immunity test.
Emission Measurements: LF Measuring System
Test System Overview
Test System Features
LF Measuring System has many unique and outstanding features:
- Utilises public power main
- Light weight and transportable
- Unique power amplifier design (patent pending)
- 4000VA rated system
- 250V maximum EUT supply
- 16A per phase maximum EUT current
- Power source continuously monitored for compliance
- Discrete components for flicker impedance
- Flicker measurements Pst and Plt
-dmax measurements
- Automatic Pass/Fail indication
- Powerful analysis software
- Lower cost solution compared to conventional systems
- System verification built-in
- Compact 19“ bench top or rack mount design
- Fulfills all the latest standard requirements
- Remote control and software upgrade through standard interface
- Easily expandable to 3-phase measurement system
- 2 year warranty
User Benefits
The technical excellence and many unique features of LF Measuring System translates
directly into benefits for the user
- Cost effective solution to meet many test requirements
- Increase quality of test object
- Independant of local mains supply (with separate AC source option)
- Save operator time with the automated test routines and test report facility
- Easy retrieval of test data
- Unparalleled reliability and system up-time
- Test Assistant
Emission Measurements: LF Measuring System
System Components
The Low Frequency measuring system is a compact solution to determine harmonic
and flicker emissions generated by equipment connected to the public power main.
HAR1000-1P is the single phase version and comprises a power amplifier, line impedance network, harmonics and flicker measurement, all in a single unit. HAR-EXT1000
added to HAR1000-1P provides full three phase capability.
The hardware is controlled from a powerful user interface software (HARCS).
Power Amplifier
Using a novel technique to correct power main distortion reduces size, weight and
cost compared to traditional systems. A small power amplifier is used to correct power
main distortion and deliver a clean sine wave to an EUT. While the measurements are
being made, the test voltage (U) at the terminals of the equipment under test, when
operated according to the defined operating condition, shall meet the requirements
laid down in the IEC standards.
The power amplifier source impedance must be nearly 0ohm to prevent distortion of
flicker results. The test voltage must be stable in amplitude and frequency to ensure
correct results.
Line Impedance Network
Flicker measurements are small variations of RMS voltage caused by the EUT. In order
to ensure that only effects from the EUT are measured, a conventional impedance of
0,4ohm + j 0,25ohm must be used. This is a real impedance included in the system.
Emission Measurements: LF Measuring System
Harmonic Measurement System
This can be configured to measure in accordance with the latest standard requirements (including amendment 14) and also the previous version. Providing an easy
comparison of measurement results obtained from previous and new samples. Dual
analysers simultaneously monitor the AC supply output and the distortion resulting
from the EUT. Both voltage and current harmonics are measured and displayed for
analysis purposes
Definition of the equipment classes
Display of single phase harmonic voltage and
current (left)
Harmonic results table including real time EUT
measurements (right)
Emission Measurements: LF Measuring System
Flicker Measurement System
The flicker analyser is a part of the system hardware and is compliant to the latest
requirements of IEC61000-4-15. Specifically this means that dmax is the result of an
average from 22 measurements taken from a total of 24. Verification of the flicker
measurement system can be made using 33.3Hz modulation for 50Hz and also 40Hz
modulation for 60Hz supplies. The inrush current capability enables measurement of
dmax at 7%.
Graphic representation of cumulative probability function. The real time flicker value is
displayed together with all the measurements
required for standard compliance. (left)
Display of dmax value showing amplifier in-rush
capability (right)
HARCS software
Provided as part of the system package, HARCS software is a powerful user friendly
interface which allows the user to configure the system to perform measurements
and displays the results in a convenient format. Unique features of HARCS software
- Test Assistant
- Harmonics inspector
- Recorder function
- Harmonic verification
- Flicker verification
Upgrading the HARCS to include the immunity package, provides a low cost means
to perform additional testing for harmonic immunity, voltage fluctuations and ripple on
DC supplies.
Test Assistant
Harmonics Inspector. Select individual harmonics to view additional information in real
Emission Measurements: LF Measuring System
HARCS Recorder. Up to 8 different measurement parameters can be stored in the recorder. When a test is completed, data from the
recorder can be “re-run” to assist in analysis
of measurement results.
HARCS ANASIM. Included in the HARCS package is the simulation program ANASIM.
Verification. Perform a quick system verification for harmonics and flicker using internally
generated signals.
Emission Measurements: LF Measuring System
Generator Specifications
Power Amplifier
Power rating
Amplifier bandwidth
Voltage range (230V)
Voltage range (115V)
Continuous current
Usable supply frequencies
Inrush current
Load change regulation
Total Harmonic Distortion (THD)
Response time 0 to 100% load change
Voltage harmonic distortions
Source impedance
DC to 6000Hz
200 to 250V
100 to 125V
500A at 230V
< 0.05%
< 0.5%
3rd harmonic < 0.9%
5th harmonic < 0.4%
7th harmonic < 0.3%
9th harmonic < 0.2%
2nd - 10th harmonic < 0.2%
11th - 40th harmonic <0.1%
< 3mohm
Harmonic Measurement System
Current and Voltage harmonic range
Harmonic class measurements
Frequency measurement accuracy
Voltage drop across current shunt
Current ranges
Current measurement accuracy
Parameter measurement and display
FFT of EUT current
Fluctuationg harmonics
1st to 40th harmonic
A, B, C, D & X
< 0.1%
< 150mV
auto, 0.25A, 0.5A, 1A, 2A, 5A, 10A,
25A & 50A
< 1%
Urms, Upeak, Irms, Ipeak, Crest factor, Power, Apparent power, Frequency, UTHD & ITHD
real time 4096 points over 16 periods
16 periods (50 or 60Hz) with 1.5s filter
Flicker Measurement System
50Hz Line Impedance Network 1 phase
50Hz Line Impedance Network 1 phase
50Hz Line Impedance Network 1 phase
50Hz Line Impedance Network 3 phase
50Hz Line Impedance Network 3 phase
Flicker meter
Flicker measurements per second
Parameter measurement and display
Flicker dislays
Automatic Pass/Fail indication for
0.4ohm + j0.25ohm (phase & neutral)
0.24ohm + j0.15ohm (phase only)
0.16ohm + j0.10ohm (neutral only)
0.24ohm + j0.15ohm (phase only)
0.16ohm + j0.10ohm (neutral only)
according to IEC61000-4-15
Urms, Irms, Power, Power factor, Frequency, Pst, Plt, dmax, dc & dt
Cumulative probability, histogram
Pst, Plt, dmax, dc & dt
Mains Supply Requirements
± 10%
± 0.5% for 9A range and 16A range
Emission Measurements: LF Measuring System
Accessories and Options
HAR1000-1P can be enhanced with the following accessories:
HAR-EXT1000 with
HAR1000-1P and
Adds two further phases to the HAR1000-1P. Simple connection without any hardware
modifications mean this powerful extension can be added at any time to an existing
single phase system.
Simultaneous display of three phase
HARCS Immunity Software
This package can be added to the single phase system. It extends the system’s emission capability to include power line immunity tests such as harmonic immunity and
voltage fluctuations.
Easy selection of test sequences (left)
Immunity measurement of one phase system
in real time (right)
Low cost power source to provide alternative supply to local main. PS3-1 is available
with up to 3 voltage/frequency combinations.
USB Serial Cable
The UC-232A USB Serial adapter provides an external plug-and-play RS-232 serial
connection for computers and notebooks that support USB specification.
Emission Measurements: LF Measuring System
EMC PARTNER’s Product Range
The Largest Range of Impulse Test Equipment up to 100kA and 100kV.
Immunity Tests
Transient Test Systems for all EMC tests on electronic equipment. ESD, EFT,
surge, AC dips, AC magnetic field, surge magnetic field, common mode,
damped oscillatory and DC dips. According to IEC and EN 61000-4-2, -4,
-5, -8, -9, -10, -11, -12, -13, -14, -16, -18, -19, -29.
Lightning Tests
Impulse test equipment and accessories for aircraft, military and telecom
applications. Complete solutions for RTCA / DO-160 and EUROCAE / ED-14
for indirect lighting on aircraft systems, MIL-STD-461 tests CS106, CS115,
CS116 and Telecom, ITU-T .K44 basic and enhanced tests for impulse,
power contact and power induction.
Component Tests
Impulse generators for testing; varistors, gas discharge tubes (GDT), surge
protective devices (SPDs), X / Y capacitors, circuit breakers, watt-hour meters, protection relays, insulation material, suppressor diodes, connectors,
chokes, fuses, resistors, emc-gaskets, cables, etc.
Emission Measurements
Measurement of Harmonics and Flicker in 1-phase and 3-phase electrical
and electronic products according to IEC /EN 61000-3-2 and 61000-3-3 .
HARCS Immunity software adds interharmonic tests, voltage variation and
ripple on DC tests according to IEC/EN 61000-4-13, -4-14.
System Automation
A full range of accessories enhance the test systems. Test cabinets, test pistols, adapters and remote control software, simplify interfacing with the EUT.
Programmable PSU, EMC hardened for frequencies form 16.7Hz to 400Hz.
Frequency PS3-SOFT-EXT complies with IEC / EN 61000-4-14 and -4-28.
Our committment starts with a quality management system backing up
our ISO 17025 accreditation. With the SCS number 146, EMC PARTNER
provide accredited calibration and repairs. Our customer support team are
at your service!
Emission Measurements: LF Measuring System
For further information please do not hesitate to contact EMC PARTNER’s representative in your region. You will find a complete list of our representatives and a lot of other
useful information on our website:
The Headquarters in Switzerland
Baselstrasse 160
CH - 4242 Laufen
Phone: +41 61 775 20 30
Fax: +41 61 775 20 59
Email: sales@emc-partner.ch
Web-Site: www.emc-partner.com
Your local representative
Information and specifications in this document are an indication of capability only. Technical performance is given in the EMC
PARTNER AG Technical specification for the corresponding instruments.Version 11.2016. Subject to change without notice. .
Emission Measurements: LF Measuring System
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