Introduction to EMC

Goals

formation-objectifs-seointro 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