“ Presentation is important, the grandeur and opulence and the fresh clear-cut feel of your building is superb. Along with the new facilities it is exactly what we wanted for our testing. We are testing to stringent spec and the automotive connection here is important to us! In the past we have built up a good relationship with 3C through e mails and quite complex negotiations regarding our requirements. I enjoy coming here. ”
“ I would like to thank you for your time yesterday, very much appreciated and I would like to say how impressed I was with your company structure and layout. Look forward to seeing you in the near future with some new products. ”
“ We are very happy with the service and co-operation we get here. It's a two-way thing. Improvements? No improvements to suggest really, we get just what we need. ”
“ We found 3C Test on the Internet, we liked the look of the building and your wording on the website was very clear. Your facilities are very good and your engineers helpful, no improvements, I am very pleased with everything. ”
“ We do EMC testing fairly frequently, we have always used 3C Test, even when you were at Grendon, good lot of guys here, we are happy with the testing, that's why I always come back! ”
“ Of all the Test Houses we use we get the best progress, best technicians and best accounts dept from 3C Test, also the best coffee. ”
EMC Testing Services at 3C Test have developed through customer demand. Ability to recognise your technical product developments, in conjunction with the global market place, puts us in an ideal position to assist you with relevant and effective design for market compliance. When thinking of compliance testing, minimal disruption to production, marketing deadlines and budgets is a major factor and at 3C Test Ltd our services can be tailored to meet your requirements.
Pre-compliance testing is a cost effective way of ironing out potential problems before the required full compliance testing and subsequent final certification and an early diagnosis of potential EMC problems through pre-compliance testing can reduce manufacturing costs and failures in the field. 3C Test have invested in major improvements, thereby keeping pace with technology and provide a friendly, flexible approach, supported by experts, to assist throughout the entire EMC compliance process.
We offer specialist testing services from DC for Emissions and field strengths up to 600V/m for Immunity. We cover Military, Commercial, Medical, Automotive, Agricultural, Space, Marine, Rail, Aerospace, Industrial, IT, and Telecom equipment. Please contact us and talk to our experienced EMC specialists to discuss how our facilities can be used to support your test requirements.
GLOSSARY OF EMC TERMS
360 bonding |
Bonding all around the perimeter of a cable shield or around the periphery of an aperture in a shielded enclosure. |
Adjacent channel interference |
Radio interference located close in frequency to the operating channel of a victim receiver. |
ADF |
Automatic direction finding. |
ADSL |
Asymmetrical Digital Subscriber Line is a method of delivery of broadband data over telephone lines. |
AM |
Amplitude modulation. |
Amps/metre or A/m |
A unit for the measure of magnetic field strength. |
ASD |
Adjustable speed drive |
B |
Magnetic flux density. |
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Bluetooth |
A wireless technology for the short-range interconnection of ITE, operating around 2.45GHz, originally intended as a cable replacement for printers, keyboards, and other PC peripherals. |
Bonding |
In EMC terms, the electrical connection of two or more conductors together to equalise their potential. |
CAA |
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CAD |
Computer aided design. |
CB |
Citizen\'s band, a radio communications system operating around 27MHz. |
CCIR |
International Radiocommunications Consultative Committee. |
CCITT |
International Telegraph and Telephone Consultative Committee |
CCTV |
Closed circuit television. |
CE Mark |
A mark affixed to products marketed in the EU, showing that equipment complies with applicable EU Directives. |
CEN |
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CENELEC |
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Characteristic impedance |
The ratio of voltage to current of a conducted RF signal, at a point on the conductor. |
CISPR |
International Special Committee for Radiofrequency Interference (sub-committee of IEC). |
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CMR |
Common mode rejection. |
Coaxial cable |
Form of cable construction in which the inner conductor is surrounded by a tubular screening sheath on the same axis. |
Co-channel interference |
Radio interference located on the same frequency as the operating channel of a victim receiver. |
Common mode |
A voltage or current that applies identically to all the conductors (including return conductors and shields) associated with a cable, or with an item of equipment. |
Conducted (emissions, transients) |
Unwanted energy conducted from equipment via the power supply or signal cables. |
COTS |
Commercial-off-the-shelf describes equipment procured for specialist applications such as defence, aerospace or marine but which is only intended, certified and marketed for commercial use. |
Declaration of Conformity (EU) |
A document created and signed by a manufacturer or importer into the EU, which makes various legal statements concerning the compliance of an equipment with applicable EU Directives. Mandatory for all CE marked products. |
Demodulation |
Recovery of the original information (speech or data) that was modulated onto a radio frequency signal. |
Diathermy |
A medical technique involving the heating of body tissue by the application of RF energy. |
Differential mode |
A voltage or current that applies between pairs of conductors (signal and return). |
Disturbance |
Unwanted EM energy, which may or may not affect victim equipment. Disturbances may be produced by either intentional or spurious sources, from equipment, or by natural causes (e.g. lightning, or electrostatic discharge). |
dop |
The latest date of publication of an identical national standard. |
dow |
The latest date of withdrawal of a conflicting national standard. |
DTI |
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EC |
European Commission |
EEA |
European Economic Area. |
Electromagnetic Compatibility (EMC) |
The ability of an equipment or system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances into that environment. |
Electromagnetic environment |
The totality of the electromagnetic phenomena existing at a particular location. |
Electrostatic discharge (ESD) |
A sudden transfer of static electric charge from one body to another. The dissipation of the charge causes transient disturbing currents and electric fields, which are a source of wideband radiated emissions. |
EM |
Electromagnetic. |
EMC |
See Electromagnetic Compatibility |
EMF |
Electromagnetic fields. |
EMI |
Electromagnetic interference. |
EM wave |
The direction of the energy transfer by an EM field. |
EN |
European Norm/European Standard, a technical document written by CEN, CENELEC or ETSI. |
ERP |
Effective radiated power. |
ETSI |
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EU |
European Union. |
FAA |
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Far field |
Further than a certain distance (approximately one-sixth of a wavelength) from an emitting source. |
FCC |
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Filter |
A capacitor, inductor or resistor, or some combination of capacitors, inductors and/or resistors, intended to reduce the amount of electromagnetic energy at unwanted frequencies from being conducted along a cable or wire. |
FM |
Frequency modulation. |
Frequency |
The rate at which a repetitive event happens, measured in Hertz (or kHz, MHz or GHz). |
GHz |
GigaHertz: 1,000,000,000 Hertz. |
GPS |
Global Positioning System, a network of low-earth-orbit satellites created and maintained by the US military for world-wide navigational purposes. |
Grounding |
In EMC terms, the interconnection of conducting structures to present a low impedance reference for signal or filtering circuits. An EMC ground may or may not be at the potential of the earth mass, and is not necessarily the same as the safety earth or protective conductor. |
GSM |
Global System for Mobile communication: the most common pan-European mobile phone system; the acronym refers both to the service and to the technical specification which underlies it. |
GTEM cell |
An enclosed transmission line structure used for EMC testing. |
Harmonics |
Frequencies which are an integer multiple of the fundamental frequency. |
H |
Magnetic field strength. |
Hz |
Hertz: unit of frequency, one cycle per second. |
HF |
High frequency (3MHz -30MHz). |
HSE |
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Interference |
The result of inadequate immunity to disturbances. |
Intermodulation |
The interaction of signals at multiple frequencies in a non-linear device or environment, which generates frequencies that were not present in the original sources. |
I |
Current. |
IC |
Integrated circuit (the silicon chip) |
IEC |
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IEE |
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IEEE |
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IF |
Intermediate frequency. |
I/O |
Input/output. |
Induction |
Coupling into a circuit by electric or magnetic fields, in the near field. |
ISDN |
Integrated Services Digital Network. |
ISM |
Industrial, scientific and medical. |
ITE |
Information technology equipment. |
ITU |
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kHz |
kiloHertz: 1,000 Hertz. |
LCL |
Longitudinal Conversion Loss -a measure of the conversion between differential and common mode in balanced cable pairs. |
LED |
Light emitting diode. |
LF |
Low frequency (30kHz - 300kHz). |
LORAN-C |
Long range navigation system. |
LPRA |
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MF |
Medium frequency (300kHz -3MHz). |
Metallic |
Using a conductive method to transfer EM energy or signals (e.g. metallic communications as distinct from wireless communications). |
MHz |
MegaHertz: 1,000,000 Hertz. |
Mode stirred chamber |
A screened chamber used for EMC testing in which the EM field is made uniform by a rotating metal or metallized paddle. |
NATS |
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Near field |
Within a certain distance (approximately one-sixth of a wavelength) from an emitting source. |
NRPB |
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OATS |
Open area test site. |
OJEC |
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PC |
Personal computer. |
PCB |
Printed circuit board. |
PED |
Passenger electronic device (in the context of civil airliners). |
PLC |
Power line communications, an alternative acronym for PLT, see below. |
PLT |
Power Line Telecommunications or Power Line Technology - a method of delivery of broadband data over power supply lines. |
PMR |
Private Mobile Radio. |
PWM |
Pulse width modulation. |
Q |
The quality factorof a resonance, the ratio of the frequency at the peak to the bandwidth at its -6dB points. |
Radiated emissions |
Energy transmitted as EM waves. |
RA |
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RAKE |
Radio activated key entry (generally, keyfobs for vehicles). |
Resonance |
Frequency-selective phenomenon in which a peak in response or coupling is experienced around one or more particular frequencies. |
Reverberation chamber |
A screened chamber used for EMC testing in which the EM field is made uniform by a rotating metal or metallized paddle. |
RF |
Radio frequency. |
RF bonding |
In EMC terms, the electrical connection of two or more conductors together to equalise their potential at RF. |
RFI |
Radio frequency interference. |
RIS |
The RAs Radio Investigation Service. |
RSGB |
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Screening |
An alternative term for shielding. |
Shielding |
The use of conducting material to form a barrier to EM waves, so that they are reflected or absorbed. |
Transient |
A rapid change of the waveshape of voltage, current, or field, of very short duration followed by a return to steady state. |
Transmission line |
A metallic communication in which the characteristic impedance of the conductor is maintained at a particular value. |
SMPS |
Switched mode power supply. |
STI |
Surface transfer impedance. |
TEM |
Transverse electromagnetic mode. |
TETRA |
Trans European Trunked Radio Access a digital pan-European private mobile radio system. |
THD |
Total harmonic distortion. |
TTE |
Telecommunications terminal equipment. |
UHF |
Ultra-high frequency (300-3000MHz). |
V |
Volts. |
VCCI |
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VDSL |
Very high speed Digital Subscriber Line (see ADSL). |
VDU |
Visual display unit. |
VFD |
A type of VSD in which the PWM output creates a variable frequency sine wave to control the speed of an AC motor. |
VHF |
Very high frequency (30-300MHz). |
Volts per metre (V/M) |
Measure of electric (electromagnetic) field strength. |
VSD |
Variable speed drive. Also known as ASD. A motor drive using switched-mode power conversion techniques to generate a PWM output to control the rotational speed of an electric motor. |
VSWR |
Voltage standing wave ratio. |
Wave impedance |
The ratio of electric field to magnetic field of a radiating RF signal, at a point in space. |
Wavelength |
Distance between adjacent peaks of an EM wave: related to frequency by: wavelength (metres) = 300 / frequency (MHz) |
Wi-Fi |
A wireless technology for the short-range interconnection of ITE, operating around 2.45 and 5GHz. |
Wireless |
Using a radiated method to transfer EM energy or signals (e.g. wireless communications as distinct from metallic communications). |
Zigbee |
A wireless technology for the short-range communication of data and control signals. |