Introduction to EMC

Goals

The objectives of the training Introduction to EMC :

- Understand the challenges of EMC

- Acquire a solid foundation through an overview of the phenomena and parameters of this discipline

The aim of this training course is to:

• Discover EMC vocabulary


• Be able to analyse the behaviour of equipment: disruptors, victims


• Be able to analyse the couplings between source and victim


• Understand the different standards and tests

Program

1/ Introduction
EMC definitions and vocabulary
Conducted disturbances, radiated disturbances
Electromagnetic fields
Radiated power, propagation, reciprocity
Relative units in dB


2/ Intentional sources of interference
Frequency bands of common radio transmitters
The Nuclear Electromagnetic Pulse
Characteristics of ‘Bell’ and ‘CEI’ waves
Comparison between lightning and NEMP


3/ Unintentional sources of interference
Lightning: physical mechanism
Electrical characteristics, standardised wave
Keraunic levels
Elevation of ground potential: potential dome
Protection of a building against lightning by a lightning conductor (electrogeometric model)
Electrostatic discharges
Sensitivity of components
Antistatic chain
Surge voltages when relay contacts open
Radiation from digital equipment
Switching power supplies
Installation of variable speed drives
Limiting disturbances at source


4/ Victims
Victims of EM fields
Envelope detection of analogue circuits
Biological effects of radio waves
Interference with a radio receiver, intermodulation


5/ Conduction coupling Galvanic isolation Common impedance coupling Capacitive and inductive crosstalk Surge protection
Protective devices
Sparks and varistors
Mixed couplings
Lightning arresters
Principle of layered protection


7/ Interference filtering and filters
Interference filters: roles and specifications
Structure and specific features of EMC filters
Filtering connectors and power filters
Use of ferrite cores
Signal processing


8/ Shielded cables: transfer impedance
Definition of transfer impedance
Transfer impedance of cables and connectors
Connection of cable shielding


9/ Radiation coupling
Fields from portable transmitters and receivers
Risks from EM fields, orders of magnitude


10/ Shielded enclosures
When is a screen necessary?
Reflection / Absorption
Shielding effectiveness
Influence of openings
Electrical continuity

11/ Installation Earth and grounding networks / uniqueness Earth connection, Tellurohmmètre principle Interconnection of systems Definition and effects of ground loops and between grounds Measurement

Narrowband, wideband

Radiation/conduction emission

Measurement receivers, spectrum analyser

Antennas, antenna factor

Magnetic/electric field measurement electric fields

Current measurement on cables

Voltage measurement using R.S.I.L.

13/ European directive

Essential requirements of the EMC Directive 2014/30/EU

Competent and notified bodies

Generic standards, product family standards, product standards

EMC standardisation bodies

14/ Standards

Test classification

CISPR limits and measurement methods

Emission and immunity standards

IEC/EN 61000-4-2 to 61000-4-11

French and foreign military standards