Introduction to Electromagnetic Compatibility (EMC) for Open Day 18 September 2013 Presentation by Pete Dorey. TÜV Product Service

Transcription

1 Introduction to Electromagnetic Compatibility (EMC) for Open Day 18 September 2013 Presentation by Pete Dorey 1

2 Content Overview of Electromagnetic Compatibility (EMC) EMC Design EMC Examples EMC Directive EMC Standards EMC Testing 2

3 Overview of Electromagnetic Compatibility 3

4 Problems at Home Television Interference Radio Interference Telephone/Telecom Interference Computer crashing 4

5 Coupling Mechanisms far-field radiated conducted near-field induced (capacitive or inductive) 5

6 Radiated Coupling Field enters equipment via apertures, seams, non-conductive parts etc. Radiated Field Coupling Displays Controls Field induces interference on cables into equipment Power Signal Equipment Crosstalk from adjacent cable 6

7 Conducted Coupling Displays Controls ESD Power supply harmonics, transients, LF & RF noise Equipment Ground lead induced noise & transients, common ground impedance Power Signal Induced noise and transients, noise from connected equipment 7

8 Types of Interference Continuous Interference observed in the Frequency Domain e.g. with Spectrum Analyser Transient Interference observed in the Time Domain e.g. with Oscilloscope Amplitude Amplitude Frequency Time 8

9 EMC Design 9

10 Earthing, Grounding & Bonding Rear of Rack Rear of Rack Rear of Rack Equipment Equipment Equipment Equipment Equipment Equipment Copper strap or braid Bonding Copper strap Grounding Single Point Earth Earthing 10

11 Filtering and Suppression Blocking Limiting RF Choke Snap on Ferrite Inductors Bypass Gas Discharge Tube (Comms) Hybrid Metal Oxide Varistor Transient Suppressor Capacitors Power Line & Bulkhead Filters 11

12 Filter Mode + Differential choke Differential capacitor circuit Differential mode filter Common-mode choke + Common-mode capacitors circuit Common mode filter GND 12

13 Surge Protection Devices Surge Protection Devices (SPDs) Used in power circuits as well as communication circuits Protect equipment from transient, high-frequency disturbances in the form of surge voltages or surge currents typically caused by lightning SPDs are designed for mitigating surges that occur as single events (possibly as bursts) in a random, generally unpredictable manner. SPDs are often used in combination with filters.

14 Shielded Cables, Glands and Connectors Screened / Shielded Cable Screened Plug (not plastic!) Screened Socket grounded to chassis (no paint!) 360º bond around periphery of connector (low impedance) e.g. Soldered, clamped or compression spring NO PIGTAILS! 14

15 Cable Containment Cables are one of the main mechanisms for coupling of interference into and out of equipment IEC , EN and BS7671 IET Wiring Regulations provide guidance on EMC separation of cables The message - Keep power cables and signal cables separated

16 Shielding RF Enclosures & Shielding Shielded 19 Cabinet 16

17 EMC Examples 17

18 Robotic Paint Booth Example A major manufacturer of automotive parts commissioned a series of robotic paint booths to save cost, it was agreed that the cabling would be installed by contractors

19 Robotic Paint Booth continued... The paint booths suffered random (and sometimes dangerous) faults 80% of the shielded cables had to be replaced this time using correct shield termination methods

20 Robotic Paint Booth continued... The supplier had not provided any instructions on the correct termination of the screened cables so, after protracted legal arguments, he picked up the bill for the modifications and also had to pay the penalty clauses in the contract $

21 Industrial Fastener Production Radiated Field Packaging Cell with Automatic Weighing Machine RF Welder to Seal Packets >25% errors = 4k per shift Unrestricted radiation at Industrial/Scientific/Medical frequencies; 13.56MHz, MHz The Manufacturer lost 6 weeks production, suffered additional costs, and lost credibility with their major customer

22 Crane Hoist Load Cell Radiated Field from Walkie Talkie Random Load Cell Output 0-10V Solution - Prohibit use of Radios on Crane!

23 Plastic Moulding Drive M Radiated Interference ºC Solution Shielded Motor Drive Cable Variable Speed Drive EMI Filter Conducted Interference Temperature Sensor Loss of temperature control deformed parts s Power Distrubution

24 EMC Directive 2004/108/EC 24

25 EMC Directive 2004/108/EC EQUIPMENT APPARATUS FIXED INSTALLATIONS Any finished appliance or combination thereof A particular combination of apparatus used permanently at pre-defined locations The EMC Directive does NOT address safety. 25

26 What is Apparatus? 26

27 Includes Mobile installations Mobile installations are defined as a combination of apparatus (and where applicable other devices) intended to be moved and operated in a range of locations are deemed to be apparatus. All provisions of the EMC Directive, as defined for apparatus, apply to mobile installations. 27

28 What is a Fixed Installation? 28

29 EMC Directive Exclusions Equipment covered by Directive 1999/5/EC on Radio and telecommunications terminal equipment (R&TTE) Aeronautical products as referred to in Regulation (EC) No1592/2002 Radio equipment used by Radio Amateurs Benign equipment (e.g. passive, cables, switches etc.) Excluded components (e.g. discrete components, assemblies not intended for the end user) Equipment where essential requirements are laid down in other Directives; e.g: Marine Equipment Directive (MED) 96/98/EC Automotive & other Vehicle Directives Medical Device Directives Note: Military equipment is not excluded 29

30 EMC Essential Requirements Essential Requirements include the Protection Requirements such that Equipment shall be designed and manufactured to ensure that: the EM disturbance generated does not exceed the level above which radio and telecommunications equipment or other equipment cannot operate as intended; it has a level of immunity to the EM disturbance to be expected in its intended use which allows it to operate without unacceptable degradation of its intended use 30

31 Enforcement In the UK the EMC Directive is enforced by OFCOM and Trading Standards under the UK Regulations SI 2006 No 3418 The maximum penalty for the supply of non-compliant equipment is: Three months imprisonment and/or A 5000 fine More normally the manufacturer would be required to recall or replace any non-compliant apparatus. The enforcing authorities have the power to suspend or prohibit sale of apparatus for which they have reasonable evidence that it does not comply. 31

32 New EMC Directive Amendments New Directive due 2013/2014 Will have a transition period New UK regulations will apply Optional use of Notified Bodies as before - New accreditation criteria, will operate as type examination bodies, NB will track and inform manufacturer of changes in harmonised standards New obligations for importers Check and hold DoC and provide access to Technical Documentation New obligations for distributors Check product CE Marking, name & address of manufacturer/ importer Product traceability requirements Identification link to Technical Documentation, record of supply or receipt Single EU Declaration of Conformity to include all relevant Directives No change to technical scope or essential requirements

33 Apparatus Conformity Procedure Declaration of Conformity CE Marking 33

34 Example DoC SUPPLIER S DECLARATION OF CONFORMITY Number of DoC: Issuer s name Object of declaration: Electronic Emission Presentation B.V. Immunity Street 2 Emission City Belgium Seminar Presentation Machine Honshu Model de Luxe The object of the declaration described above is in conformity with the requiremen5ts of the following documents: Document No. Title: 2004/108/EC EU EMC Directive (2004) EU Harmonised standards EN 88099:2009 EN 99099:2010 EN 99088:2008 Part X except Chapter Y EEP test method:2009 Additional Information: Signed for and on behalf of: Test method XYZ. To cover the parts of EN not being applied A Technical Documentation nr. Global Presentation nr. YZZ is available to document compliance of the excluded part of the harmonised standard Electronic Emission Presentations B.V. Date: 16 June 2010 Name and function: Mr.E Veen, Managing Director 34

35 Fixed Installation Specific Requirements EMC Directive Annex I(2) Essential Requirements includes for fixed installations: A fixed installation shall be installed applying good engineering practices; and respecting the information on the intended use of its components, with a view to meeting the protection requirements (control of electromagnetic disturbance and immunity). Such good engineering practices shall be documented. The RESPONSIBLE PERSON in relation to a fixed installation shall hold such documentation at the disposal of the enforcement authority for inspection purposes for as long as the fixed installation is in operation.

36 Certain Apparatus Requirement EMC Directive Article 13(1) allows an exception for apparatus not otherwise commercially available To qualify apparatus must have a direct link from apparatus manufacturer to the fixed installation Does not require: Conformity assessment (test) Declaration of Conformity CE Marking Does require documentation: Type, batch, serial no Name & address of manufacturer ID of fixed installation EM characteristics of fixed installation (e,g industrial) Precautions to be taken for incorporation in order not to compromise fixed installation conformity

37 EMC Standards 37

38 Harmonised Standards Harmonised standards are listed on EUROPA website They have the number format EN xxxxxx:date Check the current issue of a selected standard (expired standards do not give presumption of conformity) Standards fall under the following general types (usually indicated in the titles): First Preference Product standards Product Family standards Generic standards Basic standards (non-harmonised, describe EMC phenomena test methods with range of limits) 38

39 Example Standards Selection of standards - CENELEC Guide 25 Guide on the use of standards for the implementation of the EMC Directive to apparatus Product family example EN IT emission EN IT immunity Generic (Used where no product standard is suitable) EN Residential, commercial, light-industrial immunity EN Industrial immunity EN Residential, commercial, light-industrial emission EN Industrial emission Basic Standard Some harmonised EN Harmonic emission EN Voltage changes, fluctuation & flicker 39

40 EMC Testing 40

41 Conducted Emissions Equipment under test Artificial Mains Network (AMN) Power supply input Test receiver/ spectrum analyser Power lead Voltage Measurement 41

42 Harmonics and Flicker Noise Power Harmonics - Prevents harmonic distortion, overheating of cables Flicker Noise Prevents annoying lighting flicker due to load changes 42

43 Radiated Emissions Semi-Anechoic 3m Test Facility Open Area Test Site (OATS) 43

44 Conducted Immunity Signal generator Equipment under test Power amplifier Coupling Decoupling Network (CDN) Power/ Signal input Voltage Injection 44

45 Radiated RF Immunity 45

46 Radiated Magnetic Field Immunity - Civil 46

47 Conducted Transient Immunity Lightning Surge double exponential Fast Transient Burst/ Spikes Electrostatic Discharge 47

48 Voltage Dips and Interrupts U T 0.4 x U T Gradual voltage variations t (sec) Voltage dips abrupt change at any phase angle U T U T = rated voltage Dip as % of U T, 5 cycles 100% dip, 1 cycle 48

49 In-situ Testing In-Situ Radiated Emissions 49

50 TÜV SÜD EMC Services Notified Body Assessment Technical Documentation Compilation Technical Documentation Review Guidance in conducting an EMC Assessment Guidance in applying good EMC engineering practices in Fixed Installations Technical training, briefings and support for suppliers of rail infrastructure United Kingdom Accreditation Service (UKAS) accredited test laboratory for testing both at permanent premises and in-situ Radio Frequency (RF) and Low Frequency (LF) electromagnetic field surveys Power Quality measurements 50

51 Additional Training Courses and Webinars Training Courses EMC Design - 3 days EMC Compliance of Military & Avionics Equipment - 1 day RF & Microwave Radiation Safety Course - 2 days Keep up-to-date

52 Training Summary Overview of Electromagnetic Compatibility (EMC) EMC Design EMC Examples EMC Directive EMC Standards EMC Testing 52

53 Questions? Pete Dorey Tel: